One of Amsterdam's narrowest houses is located right across the canal from its widest.

A beautiful maze marks where three countries meet.

What might look like a cliffside sacrificial altar at first glance is actually a stone compass pointing to cities and lighthouses all around the world.

The world's largest moose statue towers above the highway between Oslo and Trondheim.

Longest road tunnel in the world features an air treatment plant and the illusion of daylight.

The world's northernmost aquarium looks like it has fallen over.

At this Arctic outpost, get to know members of the indigenous Sámi community and meet their herds.

A favorite with sightseers, this Norwegian funicular provides easy access to a stunning view of Bergen and its environs.

Cold storage for agricultural biodiversity.

Stay overnight in the world's most sleekly designed rabbit hole, free of charge.

Walk behind a 50-meter-high waterfall.

The burning of this 12th-century church kicked off a campaign of Norwegian Black Metal terror.

An intricately carved Viking church overlooks a glistening fjord.

A serpentine highway twists and turns over the treacherous Norwegian Sea.

The world's largest underwater restaurant is submerged off the southern tip of Norway.

A monument to Poland's famous alleged UFO abduction case.

The site of one of the largest prison escapes of World War II.

This antique thermometer honors the creator of the first universal temperature scale.

The hollow trunk of this 650-year-old tree was used as a hideout by two Jewish brothers during World War II.

This picturesque castle in Poland has a rich history, including a legend that ties it to lost Incan treasures.

Poland's oldest salt mine has nearly everything one needs to live underground forever.

This 13th century Gothic brick castle is the largest in the world by surface area.

A mysterious structure left behind on the Polish mountainside, sometimes called "Hitler's Stonehenge".

A tribute to the Polish insurgents who fought in the failed attempt to end their city's Nazi occupation.