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

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

This once-derelict building is now one of the most beautiful bookstores in the world.

Artistic tombs, monuments, and a beautiful "Hall of Fame" lurk inside this cemetery.

Built to repay the sins of the father, this church is home to one of the most valuable works of Western art.

A gorgeous example of 13th-century Gothic architecture.

Pilgrimage site for star-crossed lovers.

Iceland's largest lagoon is home to stunning multi-colored icebergs.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

This eye-popping Icelandic crater lake is surrounded by red volcanic rock.

The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

Medicinal spa created from the mineral-rich runoff of a geothermal power plant

The yawning maw of this pagan visage is said to bite off the hands of liars.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

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

It houses the remains of a 17th-century version of the Titanic.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

Flamboyant architecture from the turn of 20th century.

The Guardian of Tallinn.

Eighty million natural history specimens call this gargantuan museum home.

This irregularly shaped sea fortress has defended not one but three different sovereign states.

The design of this beautifully crafted building was inspired by Norwegian glaciers.

Housing the famous Norwegian ice-defying 19th century polar exploration ship.

Across the Pacific in a raft, a museum dedicated to Thor Heyerdahl's now legendary expedition.