Located 280 meters underground bunker  was built with aim to function, in case of (nuclear) war, as a Military Operations Center (Supreme  Command  Staff  shelter) and a shelter for President Tito, his family and closest associates. 

This facility, that reminds of labyrinth, with more than hundreed rooms and fully preserved inventory (that consists of numerous residential areas, conference rooms, offices and   "presidential  bloc"),  was supposed  to  provide  normal  living conditions  for  350  people  for  six months.  Until  90's  construction (which  lasted  1953-1979,  and  for which  4,6  billion  US  dollars  were invested) and the wary existance of this bunker were most strictly kept top military secret.