Many places commemorate the heroic history of Warsaw such as Pawiak, a German Gestapo prison now occupied by a Mausoleum of Memory of Martyrdom and a museum. The Warsaw Citadel, a 19th-century fortification built after the defeat of the November Uprising, was a place of martyrdom for the Poles. Another important monument, the statue of Little Insurrectionist located at the ramparts of the Old Town, commemorates the children who served as messengers and frontline troops in the Warsaw Uprising, while the Warsaw Uprising Monument by Wincenty Kućma was erected in memory of the largest insurrection of World War II.