A small but immensely extravagant palace built by the "Night King."

"The most colorful grottoes of the world.

Skeletons dressed in extravagant 18th century royal costumes cavort in the aisles of this German basilica.

Berlin's natural history museum houses the world's largest mounted dinosaur and the late beloved polar bear Knut.

A striking 12th-century-style castle built on the edge of a cliff.

A sprawling Baroque park with 300-year-old hydro-pneumatic waterworks.

The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.

Ruins of a German Castle on top of a towering stone pillar.

The most visited, and possibly most controversial, museum in Germany.

The birthplace of an eccentric alchemist and possible inspiration for the fictional reanimator of monsters.

Started as a kitchen garden, now the second largest botanical garden in the world.

A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

The fairy tale castle of the "fairy-tale king."

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

A 13th-century convent where St. Margaret of Hungary spent her teenage years.

This quaint Hungarian railway system is operated exclusively by children between the ages of 10 and 14.

This hidden art nouveau gem was designed by an architect in search of a national style.

The mummified right fist of a 1,000-year-old saint-king sits inside an ornate golden reliquary.

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.

Museum dedicated to the terror regimes of Hungary.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

Once the home of a hermetic monk, this cave now houses a small church.

A series of caves under Castle Hill that once held the prisoner Vlad Tepes, better known as Count Dracula.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.