Within Old Walls, a Breath of Fresh Air

Elke Reichel: A historic monastery complex listed as a historic landmark—the Katharinenkloster in Stralsund—was to be renovated and simultaneously transformed into a modern museum building featuring large aquariums. This required integrating building sections dating from different centuries and eras. The challenge was to integrate parts of the building and historical layers from different centuries and generations. Sensitive handling of the building fabric was essential, as the ensemble is one of the most important urban structures in the Hanseatic city of Stralsund and part of a UNESCO World Heritage Site.

Peter Schlaier: The MEERESMUSEUM in Stralsund, which has been housed in the Katharinenkloster since the 1950s, is an institution. Having grown over decades, it has become firmly anchored in the city's collective memory. It is one of the most visited museums in Germany and also enjoys an excellent international reputation as a marine science museum and large aquarium.

It was therefore important to preserve and highlight the distinctive exhibition spaces that visitors have come to know over the years, such as the nave of the Katharinenhalle with its truss structure from the GDR era—which is now itself a listed building—and the pool with water turtles, which was built in the 1990s. The clear legibility of old and new in the sense of the Venice Charter therefore presented itself as the only viable approach. Each era remains recognizable and at the same time fits into a continuum of architectural history that shapes the identity of the entire complex.

The inspiration came from a deep respect for this historic site, with its more than 700 years of history and its long-standing cultural significance.

Elke Reichel: One of the greatest architectural challenges in the project—from the initial design phase through to the choice of materials and detailing—was to create a harmonious connection between the historic monastery complex, the later additions, and the newly inserted elements: an architecture that respectfully honors the old while coherently complementing it with the new.

All additions and newer extensions to the existing building were given a uniform external appearance. Through their materials, structure, and clear abstract volumes, they blend harmoniously into the ensemble along the city wall. A copper sheet cladding—a familiar material in Stralsund, reminiscent of the roofs of historic brick churches—gives the new structure a striking yet understated appearance.. The handcrafted batten cladding defines the facade’s structure. Glazed elements connect the new structures with the existing buildings, continue the rhythm of the copper facades, and strategically open up views of the historic building fabric, such as the gable end of the nave through the glass opening on the Westhof. 

Peter Schlaier: In 2017, an anonymous international architecture competition was held featuring a distinguished group of participants, and we were awarded first prize. The jury praised particularly the concept of preserving, highlighting and revitalizing the main attractions of the museum, which has grown over decades.. The museum has now been expanded to include new attractions, and contemporary requirements for a museum building have been met and seamlessly integrated.

Elke Reichel: Particular challenges arose in the areas of historic preservation and the integration of large modern aquariums equipped with sophisticated technology. Ensuring accessibility within a complex, historic complex featuring a wide variety of floor levels was also a real challenge. Where possible, existing building structures were preserved and materials were reused: The flooring in the Westhof was created using historic granite pavers and the masonry was made from salvaged bricks. Old glazing, coat check lockers, windows, and wooden components were refurbished and reused. We only replaced railings where necessary. The tile flooring in the Katharinenhalle was preserved in its entirety.

Peter Schlaier: The overall concept of the design was retained even after the competition and carried through to the end. In terms of the details, however, all key points were discussed in depth with the client: Does the wayfinding work? Are the changes appropriate for the expected number of visitors? How can accessibility be achieved in a straightforward and practical way? What will be preserved, and which elements will be renovated? Are the new attractions positioned in a way that creates a good flow throughout the building? Everything was put to the test, especially to address the high cost pressures. As a result, the glass elevator in the aquarium—which was still included in the competition proposal—and a 360° 3D cinema were ultimately omitted for cost reasons and not implemented.