In the heart of Luxembourg's "little Switzerland" weaves a breathtaking natural sandstone canyon with a mythological past.

This giant urban staircase was built to keep the city's brave fighting men from getting waylaid in the red light district.

Central America's deepest lake is actually a volcanic caldera, surrounded by three volcanoes.

A moving memorial to the fallen and missing from WWI trenches.

A rare example of World War I trenches from the British front.

A massive, gleaming sea turtle with a rider atop its shell looks out over the horizon.

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

This centuries-old gothic monster has been converted into a sprawling, glossy bookstore.

A UFO-shaped event building originally intended to be a science museum showcasing the future.

The world's tallest boat lift stands as a massive piece of industrial tourism.

This former coal mine, now a fascinating museum, was the site of Belgium's worst mining disaster.

Somewhere there is a giant who can no longer poop, but now travelers can stay inside his anus.

This ghost town in Belgium will lose its street art when it ceases to exist.

A beautifully preserved and hidden 16th-century alleyway, tucked behind an unassuming door.

This memorial museum chronicles the apocalyptic destruction of the First World War.

After the construction of a nearby cathedral obstructed the view, the oldest belfry in Belgium was more than doubled in height.

Three floors of musical instruments coming from all corners of the world and hundreds of years of musical history.

A little sculpture with a large wardrobe.

Climb inside an iron crystal magnified 165 billion times its normal size.

The tallest church in Mechelen might have been the tallest in the world if not for a lack of funds.

A 14th-century fortified keep showcases the masterpieces of an ingenious 20th-century clockmaker.

This picturesque Umbrian city has a subterranean side that has long remained hidden.

A 16th-century horror show built in a lovely Italian garden.

A military museum, art park, mausoleum, and architectural oddity all on one fascist's estate.