Romania's triumphal arch looks out over Bucharest.

This communist behemoth is the heaviest building in the world and a legacy of a brutal regime.

A fire once nearly devoured this gorgeous 14th-century Gothic cathedral.

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

Romania's only crater lake with water as pure as if distilled.

This Romanian village may have been drowned, but it is long from forgotten.

A giant portrait of an ancient king looms over the river.

Once an opulent Art Nouveau hotspot, the Constanța Casino is one of Romania's most beautiful abandoned buildings.

The possible imprisonment of Vlad the Impaler here earned the medieval castle its nickname, "Dracula's Castle."

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

When a supermarket opened up shop within a medieval building it became protected by UNESCO on a technicality.

An ancient knight and a symbol of the city's freedom.

A wonderfully strange collection of 500+ stuffed frogs doing people things.

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

A towering spire in the fortress of Kalemegdan honors the victorious armies of Serbia during their struggles against the Ottoman Empire.

A maze of underground tunnels beneath one of the most beautiful forts in Serbia.

A Roman monument to their own civil engineering prowess.

Religious perseverance and cultural coexistence manifest in an architectural gem that multiple wars couldn't topple.

Destroyed Serbian army headquarters sits half crumbled in a largely revitalized Belgrade.

Nikola Tesla's ashes are held in a golden sphere, surrounded by his works.

This 14th century castle withstood years of battle but is now sliding off the hills into the Danube.

This easily overlooked memorial immortalizes the scars from the 1956 Hungarian Revolution.

A 19th-century artistocrat's mansion, turned into a library, hidden in a modern library.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.