The Belgian royal family's private depot now stands abandoned and forgotten alongside the tracks.

A wonderfully kitsch bookstore the size of a supermarket.

A marble Lucifer hides behind the pulpit of this Gothic cathedral.

This sprawling Belgian fort was once thought of as impenetrable but now it is simply an abandoned relic.

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

This impressive collection of skulls and bones was gathered by an ex-zookeeper who took advantage of a pig plague.

This collection of solar timekeepers includes the world's first digital sundial.

The "stairway to heaven" lookout tower was built to resist weather, arson, and the laws of physics.

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

This abandoned Belgian fortress is purposefully being left to nature.