Longest fortress system anywhere in Europe.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

Celebrated example of Ottoman architecture that also served as a site for brutal massacres.

A bridge destroyed three times: once as a ruse, then in an actual attack, and finally for the movies.

A number of craters left by fatal mortar strikes have been filled with red resin to remember those lost during the Siege of Sarajevo.

This abandoned airplane hanger is said to have once been a top secret launch facility.

The place where World War I began.

This museum preserves the hand-dug tunnel that kept Sarajevo afloat during the Serbian siege.

There's a mini version of Iguazu Falls hidden in the Balkans, and it's got a rope swing.

Bridge that died in war and was resurected.

Yugoslavia's biggest underground airport lies in ruins.

One of the most controversial statues in Romania is an emperor with no clothes.

Romania's triumphal arch looks out over Bucharest.

The European towns of Brașov and Râșnov each have proud signs reminiscent of the Hollywood sign.

This elaborately decorated, fairytale-like Romanian royal palace is one of the most striking castles in Europe.

A small town Romanian cemetery filled with darkly humorous gravestones.

A memorial museum to the political prisoners who were held at Sighet Prison, once one of the most feared places in Romania.