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

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

Made from trees and then abandoned, this fence is still growing along a path in Germany.

A stunning two-story timepiece within a medieval Brick Gothic church.

At this unusual park, domes, ladders, chairs, and more are made from trees.

Each year, Germany's "City of Dragons" slays the world's largest walking robot.

This Rococo church is known as the most beautiful village church in the world, and does not disappoint.

A collection of artworks exclusively created by the mentally ill that was almost burned by Nazi culture police.

This painted Lego bridge is the product of over a century of locomotive history.

Bursting forth from a historic German neighborhood, these day-glo palaces are now a bright fixture in the town.

This museum tells the story of lake dwellers from 4000 BC to 850 BC, replete with stilt houses and goats.

This Parisian gem is one of the most incredible ethnographic museums in the world.

This Venice bookstore has resigned itself to constant flooding by keeping its books in bathtubs and boats.

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

This historic stone bridge has an entire neighborhood clinging to its sides.

The site of the famous Nazi book burning campaign of 1933 remembers its "Night of Shame".

This Denmark theme park is part family attraction, part experimental archaeology project.

The oldest amusement park in the world has been providing a nice spot to have some fun since the 1500s.

A perfectly circular stronghold constructed in the 10th century is now a nucleus of Viking culture housing a museum, village, and reenactment of an epic Viking battle.

The northernmost point in Denmark is a turbulent sandbar created by two clashing seas.

Museum on earth sciences featuring a recreation of a famous curiosity cabinet.

This Danish rock field is actually a sprawling ancient cemetery holding the bodies of 700 Vikings.

The gilded, masterful astronomical clock will calculate time, dates, and planetary positions for thousands of years to come.

Beneath Denmark's Højbro bridge, a bronze merman and his seven sons forever mourn for the mother and wife who left them for land.