Culture

Kunstmuseum Basel, new extension, Basel, Switzerland

Owner: City of Basel, Immobilien Basel-Stadt

Client: Construction and Transport Department of the Canton of Basel-Stadt, Städtebau & Architektur, Hochbauamt

User: Department of Presidential Affairs of the Canton of Basel-Stadt, Kunstmuseum Basel

Architect: Christ & Gantenbein

Completed: 2016

Brick: D91 and D11 in custom formats

Photos: Anders Sune Berg

Concealed lighting effect

Integration of light frieze into the façade of a Swiss art museum.

Two-thirds of the way up the front of the Kunstmuseum Basel is a broad band that serves not only as a decorative frieze but also as a communicative element.

Architects Christ & Gantenbein worked with Petersen Tegl to produce custom, concave-moulded bricks that form a horizontal band in which LED lights have been mounted. The lighting is adjusted to make parts of the frieze appear flus with the rest of the façade. When selected lights are turned on, letters appear on the façade, seemingly formed by protruding bricks. However, they are, in fact, created by the contrast between illuminated and non-illuminated areas.

The lighting is digitally controlled so the text can be modifie to advertise special exhibitions, etc. The custom bricks are handmade from the same type of clay as the facing brick (K11).

The customized concave-moulded bricks form an underlying horizontal band in which LED lights are mounted in order to achieve flexibl lighting effects.

About Kunstmuseum Basel

Kunstmuseum Basel, on the boulevard St. Alban-Graben, houses the world’s oldest city council-owned art collection, which includes several Renaissance masterpieces. The original museum was built in 1936 and clad with decorative limestone bands. Christ & Gantenbein won the competition to design the extension, which was inaugurated in 2016.

The new building spans fiv storeys, two of which are underground where a passage connects the new and old parts of the museum. The three storeys above ground correspond to the height of the older main building.

The extension comprises a large volume divided into horizontal strata as if formed by geological deposits over millennia. The brick façade has no expansion joints, creating the appearance of one continuous surface. Every other brick course protrudes, producing a subtle relief effect.

The hand-made bricks of the façade vary in shades ranging from dark to light grey. This smooth shading effect is broken near the roof, where large letters appear to have been carved out of the façade in a band encircling the building. The darkest bricks are at the bottom and appears to provide a solid base supporting the lighter layers toward the top.

“The beauty is that you can’t see the LEDs – just the light on the bricks. In traditional architecture, a frieze was usually decorated with sculptures, and sculpture is, of course, all about how light and shadow fall on three-dimensional objects. Here, we explore these principles in a highly technological and adaptable way. It is a pragmatic, modern building that reflect contemporary textual modes of communication.”

Architect Christoph Gantenbein, Christ & Gantenbein

Z33, House for Contemporary Art, Hasselt, Belgium

Client: Provincie Limburg, Z33

Architect: Francesca Torzo

Completed: 2019

Brick: Custom format tiles for facades, made of German and Danish clay

Photos: Gion von Albertini

Allusion to damask linen

The custom colour in façade tile was achieved by mixing red wine, water and milk

Architect Francesca Torzo started developing a brick for the façades on Z33 by devising a colour palette for each of the remaining Beguine buildings on the site. The aim was to explore ways the new building could harmonise with its historic surroundings.

The result was a purplish-reddish hue, which Torzo recreated at Petersen Tegl by mixing red wine, water and milk. Using this colour as a reference, the brickworks combined German and Danish clay to produce a custom brick. The new façade’s bricks are rhombus-shaped, 370 mm high, 130 mm wide and 37 mm thick.

The cladding on the street-facing wall, which is solid, was carried out so that expansion joints were unnecessary. Coloured mortar creates a coherent look – almost like a damask pattern, monochrome, but with a hint of zigzag due to the rhombus-shaped bricks.

Three formats of tiles were produced in order to create the façade exactly as the architect had envisioned it.

About Z33

Z33 is in the heart of Hasselt, on a triangular plot of land surrounded by streets on all sides. In the 18th century, a semi-monastic lay order called the Beguines established a community here, and most of the buildings still survive today. Their closed external façades line the edge of the plot, while the more open façades, heavily punctuated with windows, face the large garden. Later, a gin distillery was built on part of the site and has since been turned into a gin museum. In 1958, the art museum Vleugel ’58 was built at Zuivelmarkt 33, the address from which the new gallery derives its name.

The extension to Z33, designed by Francesca Torzo, is built in brick and follows the same principle as the Beguine buildings: closed toward the street, open toward the garden. A 60-metre-long, 12-metre-high wall almost surrounds the site. The wall is interrupted only by a ridge in the middle and two openings, one of which leads into a small courtyard and continues into Z33.

The new building has two floor of exhibition space, between which is a floo housing offices It also has classrooms, a space for handling museum objects and an apartment for artists in residence.

Z33, House for Contemporary Art has been nominated for the Mies van der Rohe Award 2022

“Minor variations in the handmade bricks create a shimmering effect, and the façade will age well with few, fine wrinkles –which I love because absolutely nothing is perfect in life.”

Francesca Torzo, architect

Tobias Mayer Museum, Marbach am Neckar, Germany

Client: Hermann and Erika Püttmer, Tobias Mayer Association

Architect: Webler + Geissler Architekten BDA (planning and supervision)

Knappe Innenarchitekten (competition winners)

Completed: 2018

Brick: K11 + nine custom format bricks made of K11 clay

Photos: Lukas Roth

Seamless corners

Meticulously planned custom brickwork endows the unusual pentagonal building with the appearance of a precisely constructed block.

The museum extension is reminiscent of both the fortress towers that fascinated Tobias Mayer and the observatories in which the scientist and astronomer spent so much of his life. The extension’s irregular pentagonal footprint closely follows the construction site’s outer boundary. Due to the varied profile it was an obvious choice to use specially moulded, handmade bricks with exactly the angles required to achieve the building’s distinctive shape. Webler + Geissler Architekten designed nine different custom bricks and drew up the façade brickwork at 1:1 scale.

It was crucial that the new façade’s cladding should harmonise with the surrounding, centuries-old buildings, all of which boast the kind of beautiful patina only possible with hand-built construction. At the same time, the extension had to exist in its own right, and neither architecturally nor materially imitate the nearby plastered façades.

This careful approach is evident in the immaculately constructed brickwork that subtly wraps the corners.

Nine custom formats were produced so that the brickwork could be woven harmoniously around the many different angles in the building.

About Tobias Mayer Museum

Born in 1723, the scientist Tobias Mayer made many groundbreaking discoveries before his death, aged just 39. He was the firs to measure lunar movements and the topography of the Moon’s surface accurately, observe fixe stars and calculate the cycle of solar and lunar eclipses. Until 1981, the museum dedicated to his life and research was housed in Mayer’s birthplace, a half-timbered house from 1711. In 2018, an extension was inaugurated, increasing the exhibition area to 220 m2

The extension’s façades both relate clearly to and respect the half-timbered structure of the original museum. The ceiling above the recessed entranceway follows the upper edge of the original 18th-century stone wall. Similarly, the extension’s horizontal window is flus with and continues the baseline of the frontispiece.

“Before we decided on the bricks for the façade, we knew that Petersen makes handmade bricks. We approached the Backstein Office in Cologne and had a construcive dialogue with them about the possibilities. We designed the bricks, and Backstein subsequently communicated with the brickyard and contractor. The custom bricks arrived at the building site on time, along with the standard ones. The process was simple and uncomplicated throughout.”

Martin Webler, Webler + Geissler Architekten

CLAY Museum of Ceramic Art, Middelfart, Denmark

Client: Grimmerhus Bygningsfond

Architect: Kjaer & Richter A/S

Development, delivery and mounting of the slats: CO&LT

Completed: 2015

Brick: K48 + custom-format slats in K48 clay

Photos: Anders Sune Berg

A lump of baked clay

Brick slats in three formats form the flexibl cladding on a museum extension.

The extension to the CLAY Museum of Ceramic Art Denmark is sunk into the grass lawn and emerges from the earth in the form of a pavilion. Baked clay was an obvious choice for the façades on a museum of ceramics, but the architects also wanted to transform the heavy brick into a lightweight material that would convey a pavilion-like air.

They devised the idea of shaping and firin the clay for slats that open or close depending on how the exhibition space behind the wall is used.

The façade consists of three standard modules mounted on vertical steel frames designed by the architects, which form columns from the ground to the roof. Each column comprises fiv sets of brick slats, each made up of a random selection of 2-5 bricks. Developed in partnership with Petersen Tegl, the slats are made of red English clay, 37 mm thick, 805 mm long and produced in three widths: 56, 123 and 190 mm. At each end of the slats are grooves into which pin bolts are inserted. The slats are arranged in eight sections on each side of the building. All can be opened and closed independently, controlled by an electronic panel inside the museum.

About CLAY Museum of Ceramic Art

Since CLAY was founded in Middelfart, Funen, the museum has amassed a major collection of ceramic art from Denmark and abroad – the largest of its kind in the Nordic Region.

The museum is in Grimmerhus, a historic ochre-red building from 1857, built as a dower house for Hindsgavl Castle. The client did not want a traditional extension to the main building, so the new exhibition space is tucked away underground, with a pavilion as the only visible element.

From a distance, the pavilion resembles a precision-built treasure chest – but the nearer you are, the more uneven and handmade the rust-red brick surface seems. The rust-red hue glows more fiecely as you approach the building. Up close, on a sunny day, the wall is like a sea of flames

“Something special happens when you fie clay. It is a process that has fascinated brickmakers and ceramists for millennia – a magical transformation from sodden grey gunge to glowing gold to solid stone, finaly blossoming into a dark rush of colour. At any rate, that’s how it must have seemed in Nybølnor when the tiles for the CLAY Museum of Ceramic Art made their entrance into the world.”

Thomas Bo Jensen, professor, cand.arch., PhD

Museum of the Bible, Washington DC, USA

Client: Museum of the Bible

Architect: SmithGroupJJR

Opened: 2017

Brick: Mix of K36, K46, K4, K43 (9, 18, 64, 10%) and K36 in various customised widths

Photos: Tom Eckerle

Biblical motifs in brick

Echoing the museum’s purpose, the architects used special bricks to deploy subtle biblical images in the façade.

The Museum of the Bible involved not only the conversion and renovation of existing structures but also the construction of a brand new connecting building. The architects managed to make use of biblical references throughout.

The connecting building’s two façades utilise a mixture of four different versions of Kolumba in a muted, red-grey hue that harmonises with the brickwork on the adjacent industrial façades.

On the south façade, the long, narrow brick is laid in rectangular field in both transverse and vertical formats, while the last fiel is purely vertical. This not only endows the large surface with life and character but serves as an elegant paraphrase of the Wailing Wall in Jerusalem.

The two large bay windows on either side of the new building are clad in a bright red K36 in various lengths, laid in an uneven, ridged pattern. The architects wanted a subtle reference to the bulging and frayed edges of the pages on which the ancient Holy Scriptures were written.

According to the museum’s architect, David Greenbaum, brick was the natural material of choice: “Brick represents thousands of years of history and tradition. Brickmaking is an ancient craft, kept alive by Petersen, especially in Kolumba – the format, texture and handmade prints of which are infused with history.”

“The handmade nature and varied colour and texture of the brick express the same qualities as the priceless ancient manuscripts inside.”

David Greenbaum, architect, SmithGroupJJR

A mix of Kolumba in various reddish shades was produced in varying widths to achieve an uneven, fluted patern on the façade – a reference to the uneven and frayed edges of the handmade paper on which the ancient Holy Scriptures are written.

“Instead of resorting to dogmatic and literal biblical symbolism, we sought to convey religious and historical references by means of a subtle and sensuous architectural idiom. The idea was for the Museum of the Bible to be a palimpsest – a three-dimensional equivalent of the earliest handwritten Holy Scriptures, which bear traces of multiple revisions, additions and deletions over time.”

David Greenbaum, architect

About Museum of the Bible

The Museum of the Bible in downtown Washington DC brings to life and conveys the history, content and significanc of one of the world’s oldest and most important texts. At the same time, the modern, forward-looking approach to architecture and museums allows the museum to make its own mark on history.

The museum is housed in a red brick building from 1922, originally a refrigerated warehouse. A neighbouring building was later added to the triangular site, and then a third was built to connect the two.

The architects SmithGroupJJR were commissioned for the complex task of transforming the old industrial unit while keeping the main volume. The client wanted the site’s history and previous functions to echo in the finishe museum and for the museum’s content and non-dogmatic approach to be encoded in the architecture and design.

As well as the old warehouse, the museum complex includes a new, spectacular addition and a connecting building in red brick. The former is crowned by an asymmetrical, curved glass roof that provides a contemporary counterpoint to the old red-brick façades.

European Hansemuseum, Lübeck, Germany

Client: European Hansemuseum Lübeck gemeinnützige GmbH

Architect: Studio Andreas Heller GmbH Architects & Designers

Completed: 2015

Brick: Custom format, 305 x 105 x 65 mm, English clay. Three versions with different concentrations (30, 60 and 90%) of clay slurry on the surfaces

+ Varius custom format bricks, including roof tiles in a range of sizes for specifi solutions

Photos: Anders Sune Berg

History recreated

A key part of the project was fining a brick with textures and hues that would harmonise with the highly varied, centuries-old brickwork in Lübeck.

Studio Andreas Heller worked with Petersen Tegl to develop a unique brick for the European Hansemuseum in Lübeck. After many tests, they chose an English red clay fied at very high temperatures, with a format (305 x 105 x 65 mm) close to that used in medieval monasteries.

The architects also designed 40 moulded bricks in custom formats, including a version on the gable walls, laid in a quatrefoil pattern – a classic motif in Gothic architecture. All 120,000 bricks were made by hand in wooden moulds. The light clay slurry used as a lubricant remains in place, leaving a semi-transparent surface after firing The result is a unique brick with its own distinctive character, but that also reflect the play of colours and heterogeneous structures of Lübeck’s historic brick façades.

The custom-designed bricks for the museum were produced in three versions, the surfaces of which have different concentrations of clay slurry: 30, 60 and 90%. They were laid with the darkest at the top and the lightest at the bottom, resulting in a smooth gradation.

The architects also wanted variations to be incorporated into the new brickwork, similar to those found on old buildings that have been in use for centuries. To this end, some of the joints are fla or retracted, creating strong shadow effects. The retracted bricks are a nod to the permanent indentations in medieval façades following the removal of wooden scaffolding.

It is a Petersen hallmark that no pallet departs the brickyard until the bricks have been thoroughly mixed, which helps prevent stains and scaffolding marks. For the European Hansemuseum, Andreas Heller Architects wanted dark, irregular areas on the façades that suggest associations with modifictions and repairs to old brickwork. This makes the European Hansemuseum in Lübeck the firs project involving Petersen Tegl, for which the architect deliberately wanted the façade to look as if the bricks had not been mixed properly.

About the European Hansemuseum

The Hansemuseum in Lübeck tells the story of the famous network of traders that operated during the Middle Ages. Starting as a loose alliance in the 13th century, the Hanseatic League evolved into a powerful group of merchants and retained its power and influenc until the mid-17th century. The League consisted of 70 ports – mainly in Germany, but also London, Bruges, Bergen and Novgorod. Lübeck, which had accumulated vast wealth from the trade in silver and salt and had a strategically strong position as a shipping port for Hamburg and the Baltic Sea, was the League’s informal but undisputed centre of power.

The Hanseatic Museum is located by the River Trave at the foot of Castle Hill, the highest point of which is around 11 metres above the river. The Museum has been hewn directly into Castle Hill, where the deepest room measures 26 m. The main wing follows the river and the slight bend of the road.

The 95-metre long, 15-metre-tall monolithic edific is modulated in powerful, simple shapes reminiscent of the fortificaions that once stood here. But its modern lines and features make it very clear that this is something unmistakably new.

LAM Lisser Art Museum, Lisse, The Netherlands

Client: VandenBroek Foundation

Architect: KVDK Architecten

Completed: 2018

Brick: Custom colour K F146 (70%) and K F145 (30%) + one custom format brick

Photos: Paul Kozlowski

Floating on air

Three different customised Kolumba colours mimic shades of the surrounding park.

KVDK Architecten opted for Kolumba for LAM’s façades to reflec the horizontal nature of the museum but could not fin the colours they wanted in the standard range. Petersen Tegl is always happy to develop custom colours and formats, and the architects and client visited the brickworks several times until they arrived at just the right hues.

The surrounding Keukenhof park is notable for its trees and abundant plant life. Over several seasons, the architects collected plants and other natural objects from the park and took them to the brickworks. The staff in Broager succeeded in recreating the shades of the plants and wood cuttings and used them to develop three new bricks in nature’s own palette.

The architects also played with the opportunities that Kolumba offers in terms of designing custom formats. To the south, a path slices through the hillock. The building follows this line and is cut off at a diagonal. The pointed shape called for a custom brick, which Petersen produced. At this end, the highly tapered bricks form a sharp and precise contour, forming a wedge embedded in the hillock.

About LAM

LAM is in Keukenhof, a large park surrounding a castle, about 40 km southwest of Amsterdam. It belongs to the VandenBroek Foundation, founded by the Jan van den Broek family, owners of a big Dutch supermarket chain. The nature of their business inspired the museum’s collections: all the works refer to food and consumption, in a variety of playful, investigative and surprising ways, via media such as painting, sculpture and video art.

The area is dominated by a large, ridgeshaped hillock from the 17th century, which played a significan role in the design of the new building. From a distance, the museum seems to floa above the ground, but on closer inspection, two parallel volumes are built into and on top of the small hill, with a narrow passageway between them. Solid natural stone walls support the opening in the hillock and lead visitors into the museum through a curtain wall of glass and between the high, bark-covered pillars on which the exhibition halls rest.

Everywhere in the museum, the interior and exterior are linked. Daylight is drawn in through the windows, which provide exceptional views of the grassy hillock, the trees and the old castle. Like the Guggenheim Museum in New York, tours of the museum start at the top and then continue down through the exhibition halls, albeit with the option to crisscross the rooms.

Museum de Lakenhal, Leiden, The Netherlands

Client: City of Leiden Council

Architect: Happel Cornelisse Verhoeven

Restoration architect: Julian Harrap Architects

Completed: 2019

Brick: D190 DNF + 13 custom bricks made of the same clay

Photos: Karin Borghouts, Paul Kozlowski

Custom bricks weave old and new together

Patterns in brickwork evoke the fine texiles exported from 17th century buildings.

The extension to Museum de Lakenhal is nestled carefully between the original brick buildings. The architects, Happel Cornelisse Verhoeven, chose brick for the new buildings, too.

“D190 is blue-tempered. It’s twice-fied, with the second firin in a low-oxygen atmosphere. This imbues the brick with a greyish-yellow hue that was not available in the 17th century, but which nonetheless establishes a link to the older buildings’ grey Bentheimer sandstone detailing,” Ninke Happel explains.

“We wanted to create a building without ornamentation, but which is ornamental in its materialisation. We chose to create a sawtooth pattern of moulded brick, angled at 30°, each brick with almost the same shape as a small house. This is a north façade, which gets morning and evening sun, so the 30° angle lets the façade catch the light.”

The architects wanted to create buildings without explicit ornamentation, but which were ornamental in their material application – echoing the patterns woven into the exquisite old textiles once traded there. With these criteria in mind, Happel Cornelisse Verhoeven designed a series of custom bricks laid in varied patterns. The four-storey Van Steijn building facing Lammermarkt Square has a wide base and a narrower superstructure with four tapered bay windows, each with a profil resembling a small house, and features a sawtooth pattern of moulded bricks laid at 30°.

The north-facing façade means the angled bricks catch both the morning and evening light. The façade overlooking the Oude Singel canal features perforated moulded bricks, pulled back from the façade, alternating with custom rectangular bricks, with a runner bond laid at every second course.

About Museum de Lakenhal

Museum de Lakenhal is the city museum in Leiden. It opened in 1874 and houses a rich collection of art and crafts in a series of historical buildings built in different epochs. The oldest part of the museum is Laecken-Halle, which was built in 1641 for the purpose of inspecting the famous woollen cloth that Leiden exported around the world for centuries.

A major restoration and extension project was completed in 2019. The new Van Steijn building houses two large exhibition halls, offic facilities and a library.

The museum sought to preserve its historic buildings, which had fallen into disrepair and were marred by random alterations and extensions, offer new functions to visitors, improve accessibility and safety, make the museum as a whole more logistically coherent and offer visitors something new.

With simple, powerful effects and a feel for history’s many layers, the architects have managed to weave four centuries of architecture into the new building. The new façades’ greyish-yellow bricks and their fin textile-inspired patterns are carefully attuned to the hues and textures of the existing buildings.

Brooklyn Botanic Garden ticket pavilion, New York, USA

Client: Brooklyn Botanic Garden

Architect: ARO, Architecture Research Offic

Completed: 2015

Brick: K4, six custom bricks in the same clay

Photos: Elizabeth Felicella, Tom Eckerle

Dematerialising brickwork

Contemporary, patterned brickwork forms a counterpoint to Brooklyn Botanic Garden’s historic and beautiful archway.

For the studio Architecture Research Offic (ARO), red brick was an obvious choice for the new ticket pavilion in Brooklyn Botanic Garden. It creates a link to the exquisite, neoclassical arch nearby. “We visited Petersen Tegl and found what we were looking for in the form of the handmade K4, which has precisely the right shades of red and a distinguished Georgian look,” explains architect Stephen Cassell.

The new pavilion has a large, sloping, one-sided roof, while the rear façade, which faces Empire Boulevard, is a plain brick surface. Toward the garden, the architects have created a perforated wall that forms a screen in front of the entrance to the toilets. The idea is that the wall appears to be slowly dematerialising before stopping completely.

Large, green glass sections behind the perforated wall create a luminous signal effect. “This is a load-bearing wall with both structural and decorative functions. A big advantage of working with Petersen is the alacrity with which they produce custom bricks. We needed six different types to create the pattern we wanted as a counterpoint to the finel decorated arch,” explains Cassell.

Toward Empire Boulevard, the façade has delicately modulated corners due to the slightly serrated nature of the joints. This makes the wall an experience in itself, as it entices visitors to continue around the corner and into the garden.

About the ticket pavilion in Brooklyn Botanic Garden

Following a recent major restoration project, the famous Brooklyn Botanic Garden in New York City is now more beautiful than ever. A graceful, neoclassical arch designed in 1915 by the acclaimed New York architects McKim, Mead and White stands in the south-west corner of the garden. Facing the busy Empire Boulevard, the brick-clad arch is adorned with marble and Doric columns and was originally used as an entranceway. Over the years, its function has been reduced to a rarely used back door.

Part of the project of modernising the garden involved returning the old archway to its original prominence with the help of a ticket pavilion and toilet facilities. It was also important that the pavilion looked inviting so that people would avail themselves of its facilities, but without it overshadowing the historic archway.

The result is a square, 90-m2 building designed by Manhattan-based studio Architecture Research Offic (ARO). The elegant, modern design idiom and natural materials make the pavilion a fiting and respectful counterpart to the historic icon.

The main entrance to Tivoli Gardens, Copenhagen, Denmark

Built: 1890

Architect: Richard Bergmann and Emil Blichfeldt

Restoration project: 1990

Client: Tivoli A/S

Recreating approximately 2000 terracotta elements made of German clay for the main entrance

Photos: Anders Sune Berg

Former glory restored

Recreating the terracotta elements for the entrance to the Tivoli Gardens in Copenhagen was the catalyst for Petersen Tegl setting up its Custom Brick Department in 1990.

The Tivoli Portal, the main entrance to Tivoli Gardens on Vesterbrogade, is an archway flanked by two smaller gates, flanked, in turn, by two paviions. Every façade and surface on the iconic entranceway, which has served the same role since 1890, is clad in richly ornate terracotta.

Having lasted almost 100 years, sections of the terracotta cladding slowly crumbled, and Tivoli decided to restore the entrance in the run-up to the Garden’s centenary in 1990.

The owners approached Petersen Tegl, which did not produce custom-moulded bricks at the time. Characteristically, Christian A. Petersen accepted the commission right away – and figued out how to do it afterwards.

Petersen and the staff at Broager resurrected traditional methods used at the brickworks when it was founded in 1791. Using plaster moulds, they recreated the intricate and richly ornate bricks by hand. The Custom Brick Department was born – and supplied some 2,000 bricks in time for the Tivoli centenary.

About the main entrance to Tivoli Gardens

Georg Carstensen was inspired by parks he had seen abroad before he was granted a royal charter to open Tivoli Gardens. His amusement park was the firs of its kind anywhere in the world when it opened its gates on 15 August 1843. The famous writer Hans Christian Andersen was an early visitor.

The original entrance was a wooden gate flanke by two ticket booths – Tivoli has always charged for admission and the price of the ticket was 1 Mark. Season tickets were introduced in 1845 to encourage customer loyalty. The options were ‘gentleman’, ‘gentleman and lady’ or ‘gentleman accompanied by two ladies’.

The current main entrance and façade buildings on Vesterbrogade were completed in 1890. Both are clad in terracotta and designed by the architects Richard Bergmann and Emil Blichfeldt. The façade buildings used to be bigger and housed the Apollo Theatre and Restaurant Wivel, later known as Wivex, on either side of the main entrance. Wivex –which could seat up to 1,500 diners while big band concerts were broadcast from it – was a legendary Copenhagen venue. It closed in 1964, and the building was demolished. The portal, which still serves as the main entrance to Tivoli, was all that was left.

The Round Tower, Copenhagen, Denmark

Builder: King Christian IV

Architect: Hans van Steenwinckel (II)

Built 1637-1642

Client: Rundetaarn

Brick: Clinker made of Danish blue clay

Photos: Anders Sune Berg

Still going strong after four centuries

For the last three decades, custom clinkers have been used to replace the 17th-century originals on this famous Copenhagen landmark.

To reach the top of the Round Tower, visitors walk up an approximately 210-metre-long, step-free passage that winds around the inside of the tower 7½ times. The brick walls in the snail shelllike passage are clad in a limestone layer that varies in thickness from 300 mm to one metre. On top of this, yellow bricks were laid as clinkers with lime mortar, and many of the originals have survived.

Attached to the tower is the Church of the Holy Trinity, which houses an exhibition space on a mezzanine floo below the loft. Unfortunately, vibrations from the electric carts used to transport exhibition materials between floor for more than three decades were causing the mortar to crack. As a result, bricks were starting to protrude from the limestone and suffering damage.

Since 1990, Petersen Tegl has been supplying custom-made clinkers in Danish blue clay to repair the damage. They are laid in the same kind of hydraulic mortar used in the 17th century, which provides good adhesion and elasticity, and enables the covering to move with the rest of the building.

About the Round Tower

Built by King Christian IV in the heart of Copenhagen, the Round Tower is one of the city’s best-loved buildings and most visited tourist attractions. It is part of a complex that originally combined three very different functions: an astronomical observatory, the Church of the Holy Trinity and a university library on the mezzanine floor between he church and loft. However, due to increasing problems with light pollution from the city, the observatory moved out in 1861, as did the library.

Work on the tower began in 1637 and was completed five years later. The church was consecrated in 1656.

The Round Tower has a long and colourful history. On one occasion, the visiting Russian Tsar Peter I rode up the winding passage on horseback. His wife, Catherine I, followed in a two-wheeled carriage pulled by one horse.

The Round Tower, which was built to provide access to the observatory and a viewing platform, is a 34.8-metre-high cylindrical structure, broken up by lesenes, with courses alternating between yellow stretchers and red headers in cross bond.