The monument dedicated to the building of the Karlobag– Gospić Road across the Velebit, the Cube (Kubus, Ura) on four spheres is situated on the Oštarije Saddle or Stara vrata, at 927 m above sea level from where the view extends over Karlobag, the island of Pag and the entire Velebit Channel.

In 1846 the Cube was put up during the construction of the road from Gospić to Karlobag (1844-1850). There are 33 steps leading to the Cube. On one side of the cube there is the inscription Ferdinand I, Austrian Emperor MDCCCXLVI.