St. Ansgar’s Church was built as part of the 1957 Interbau building exhibition in Berlin’s Hansaviertel. The ground plan of the nave consists of a parabola with the altar wall at its apex. The northern parabolic arch consists of a solid wall, while the southern arch consists of vertical bands of windows divided by trapezoidal concrete frames. The supporting structure and coffered ceiling of the interior are designed as a steel skeleton construction in exposed concrete. The laterally standing campanile consists of three concrete columns, which are horizontally connected in the upper area. One support continues as a cross. The three cast steel bells of the church hang in the open belfry. The lighting concept supports the spatial effect of the church interior opening up from the chancel by increasing the luminance on the vertical surfaces defining the space from the entrance to the chancel, thus imitating the lighting effect of daylight. In order to preserve the impression, the opal glass luminaires that no longer exist were reconstructed on the basis of photographic material and equipped with modern LED technology and lighting with very good colour rendering. The facade of the church is not illuminated from the outside. In order to perceive the building at night, a small part of the interior lighting is used to backlight the glass façade on the south side of the building. The illumination of the Campanile is also limited to the visible bells in the tower. This allows the shape and structure of the building to be read by the observer from the street space even at night.