The Tabán ruins (Hungarian: tabáni romok) are a group of medieval ruins in Budapest, Hungary. They are located in District I, in the Tabán neighbourhood, between Szarvas tér and Krisztina körút. The scattered ruins officially belong to one listed monument (ID 67). The remains of the mainly medieval structures were discovered in 1936 by archaeologists after the demolition of a large part of the densely built Tabán quarter but significant parts of them disappeared in the 1960s when the whole area was restructured. A 15th-century building, named Building I, and a retaining wall by the Ördög-árok stream are still visible above ground.