The present facility, called the Roman Well, is neither Roman nor a (water) well. It is located along the southwest rampart of the Upper Town, in the vicinity of the "Pobednik" monument and the "King's Gate". An underground object existed during the mediaeval period and is referenced by Constantine of Kostenets during the rule of Despot Stefan Lazarević, in the first half of the 15th century. It apparently was a dungeon as it was mentioned during the 1456 Siege of Belgrade when 30 Hungarian conspirators died in it after their scheme to let the Turks into the fortress and surrender the city to them was thwarted. They were to be paid by the Turks, but were discovered and dropped into the pit with ropes. They were left there without food and after they began losing their minds from hunger, they were thrown knives to kill each other. Turkish traveler Evliya Çelebi in 1660 wrote about the object as the grain silo.