Also known as Rye Castle, this 13th-century fortification later became a prison and held one of Rye's most famous criminals.

One of the oldest suspension bridges in the world blends in perfectly with a medieval castle.

One of the few surviving street funiculars in the world.

Eighty million natural history specimens call this gargantuan museum home.

These paved rills bring freshwater into Altstadt and could spell wedding bells for whoever stumbles into the waters.

Model Trains and Much More in Hamburg.

Hamburgers are intensely proud of their tunnel beneath the river.

It has an American Dream Car exhibit, Europe's largest Formula One collection, and many, many mannequins.

Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.

A tower-like theater in the Swiss Alps built to withstand the high winds and avalanches of the mountain pass.

The only tower of an aerial tramway standing over a ski-lift.

The university library shaped like a giant piece of Swiss cheese.

Its vast collection of wondrous gadgets details the fascinating history of information technology.

Video games, body language, and postal history are all on display in this Swiss museum.

The largest underground lake in Europe.

A cablecar-station-turned-revolving restaurant with 360-degree views of the Swiss skyline.

A breathtaking bridge that crosses a vast gorge over a river's torrents, and has a tale of a devil architect attached.

This historic covered bridge contains a series of macabre paintings that communicate one thing: everyone dies.

The steepest classic funicular in the world glides along a dizzying incline.

This memorial commemorating fallen Swiss Guards of the French Revolution has been called the saddest stone in the world.

Caves famous for the dragon-slaying saint who lived there.

The tallest outdoor elevator in Europe rockets passengers on a dizzyingly precarious ride to the top of a mountain.

This lovely little bridge hidden in a Switzerland gorge is essentially a fairytale.

The bizarre visions of H.R. Giger, tucked away in a Swiss medieval city.