A monument to the bloody fight against fascism in Slovakia during World War II.

With its webbed walls and bright red coloring, Calgary's iconic bridge looks like a finger trap puzzle stretched across the river.

The San Marino-Rimini railroad was short-lived but this tunnel once provided shelter for hundreds of refugees during World War II.

The world's largest frame offers spectacular views of the city's past and present.

Whitewashed mosque contains the world's largest carpet.

This Yellowstone geyser may not shoot as high as the nearby Old Faithful, but it erupts for considerably longer.

The only natural lake in the world that drains into both the Atlantic and Pacific Oceans.

Around half a million years ago, these magnificent columnar basalt cliffs were formed from cooling lava.

An architect's childhood fantasy treehouse made real.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

A beautiful geyser under environmental threat.

World's strongest whirlpool.

Six turbines towering over a wide road for passersby.

This gruesome biblical parade celebrates the one day a year that a bit of Jesus' blood turns to liquid.

Each time a baby is born in Ghent, these streetlights flash in silent celebration.

This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.

Dummies recreate radiological discoveries from history.