Yuriev-Polsky's earthen mound was created in 1152 when Yuri Dolgoruky founded the city. The mound was built for defensive purposes and reaches 7 metres high. In addition a wooden fortress once stood on top of the mound but this has not survived. Since 1920 the area has been run as the Yuriev-Polsky Historical, Architectural and Art Museum. Included as part of the museum are both St George's Cathedral and the former Mikhailo-Arkhangelsky Monastery, most of the buildings of which are used to house exhibitions on the history and culture of the city and surrounding area.