The remains of the Abbey can be visited
Grey Abbey

The ruins of the monastery church in Berlin-Mitte are one of the few surviving Gothic landmarks in the city. The Grey Friars Monastery, a former Franciscan monastery, was once Berlin's most significant medieval building.
History+
The origins of the Franciscan monastery in Berlin date back to 1249. The Franciscan monks, whose grey habits gave the monastery its name, were closely connected to the Brandenburg margravial court. In 1271, Margraves Otto V and Albrecht III donated a plot of land near the city wall and their residence to the Franciscans. Another donation, a brickworks in 1290, enabled the construction of the actual monastery, which was completed in the 14th century. The monks enjoyed high esteem, reflected in numerous burial sites within the monastery, including that of Louis the Roman.
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Location: 52.5185, 13.4126