The Franciscans began to build a monastery in Gransee in about 1280. The monastery long defined the townscape and life in the town with its buildings. The monastery was closed down during the Reformation. In 1561, the monastery building was given to the town on condition that a school be set up there - students were taught here until 1963. Today, only remnants of the monastery remain. In one of the buildings, there is an exhibition that provides insights into the successful redevelopment of the town and in summer visitors have picnics on the lawn at the monastery garden.