 Complete the following phrase:  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 Kings 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 