North Rhine-Westphalia: around 800 buildings in NRW at the "Day of the Open Monument".

An old sewage treatment plant, a former postal wagon or a concrete cycle track: On Monument Day, those interested can also visit some unusual places and immerse themselves in history.

North Rhine-Westphalia: around 800 buildings in NRW at the "Day of the Open Monument".

An old sewage treatment plant, a former postal wagon or a concrete cycle track: On Monument Day, those interested can also visit some unusual places and immerse themselves in history.

Bonn (dpa / lnw) - Around 800 historic buildings are taking part in the "Open Monument Day" this Sunday. Visitors can take a look at buildings that are otherwise partially inaccessible. Guided tours or lectures are offered in many places.

In Bonn, for example, the university's old observatory, in which the night sky was systematically recorded in the middle of the 19th century, will be opened. Krefeld opens a historic sewage treatment plant from 1908. The Art Nouveau building was furnished to a high standard - although sewage treatment plants are otherwise not presentable buildings. In Marl, a former Deutsche Post railway wagon from 1974/75, which is now integrated into a house, is honored.

Bielefeld has a concrete velodrome inaugurated in 1953, which is one of the fastest in Europe and is still in use. Wuppertal illuminates the Mirke outdoor pool, which was opened in 1851 for swimming lessons and is considered the cradle of the West German swimming movement. A bunker from the Second World War is presented in Aachen.

In Cologne, numerous dates are dedicated to the Romanesque churches. Many relics of Roman times are also visible in the city, for example a 70 meter long section of the Roman city wall. They can be viewed on guided tours on Memorial Day.

The nationwide monument day under the leadership of the German Foundation for Monument Protection in Bonn is this year under the motto "Culture Track. A case for monument protection".