"A former military base for the Yugoslav National Army, the island of Vis was closed to foreigners for decades. Today, however, it’s one of Croatia’s best-kept secrets, mainly for its beaches, food, and history. Book a tour with Vis Special and explore the island’s old military sites, abandoned when the army left suddenly in 1992. The tours take in everything from rocket shelters and bunkers to weapon-storage halls and “parking lots” (read: tunnels) for submarines. They also stop at the former communications headquarters for the Yugoslavian secret service (which are dug into a mountain) and Tito’s Cave (where the erstwhile Yugoslav president hid during World War II). Lest this all sound grim, know that these sites occupy some of the most gorgeous spots on the island."