Romania's triumphal arch looks out over Bucharest.

Something's watching you.

The bust of Romania’s most notorious ruler, Vlad Dracula aka "Vlad the Impaler," keeps watch over the ruins of his medieval court.

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

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

This fairy-tale castle would make Dracula (who is said to have been imprisoned there) jealous.

This massive underground salt mine now holds a sci-fi theme park in its depths.

The Netherlands' first car tunnel has an unusually rectangular shape.

Amsterdam's former hotspot for public executions and dissections.

Devious political maneuvering and four ancient, working telescopes are central to the world's second-oldest observatory.

A true Valhalla for cactus and succulent lovers.

A 'living museum' in Leiden, the oldest of its kind in the Netherlands.

These slanted cubic abodes are a creative if odd solution to a zoning pickle.

Birthplace of the "Cat in the Cradle" and a cluster of iconic, original windmills that let the Dutch tame the seas.

This city square is home to Amsterdam's oldest church and a statue honoring Dutch sex workers.

The Jesus tree of Malta bears a striking resemblance to Christ on the cross.

Stone Age solar temple is aligned with the sun on each equinox and solstice.

The Frank Zappa fan club erected this monument to their prog-rock hero to mark a new era of post-Soviet Lithuania.

This micro-nation may be some sort of prank, but its constitution sure seems official.

Latvia's symbolic mountain-shaped national library is home to millions of cultural tomes.

The oldest housing complex in Riga is a mini timeline of architectural trends.

A black cat protests the City Guild in Riga's Old Town.

Flamboyant architecture from the turn of 20th century.

3,000 market stands in five former Zeppelin hangars.