A wonderfully strange collection of 500+ stuffed frogs doing people things.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

This scale model of our solar system hid in plain sight for years before a physics team sought out all the planets.

An eclectic art form practiced by untrained masters is celebrated at this museum in the heart of Zagreb's old Upper Town.

Where the lovelorn find a home for their sentimental keepsakes.

The "dragon babies" of southeastern Europe.

A miniature train-ride through Slovenia's largest cave system.

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

This massive subterranean fissure is known as the "underground Grand Canyon."

This Soviet-era "closed town" was a top secret uranium producer often left off of maps.

The old fire station features a mural that has more to it than first meets the eye.

The widest waterfall in Europe is a natural wonder and one of the only places where fish are caught in the air.

This small window display is dedicated to the noble carrot.

A beautiful maze marks where three countries meet.

A once-magnificent collegiate church is falling into ruin.

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

A Belgian self-built tower inspired by the Bible and ancient civilizations.

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

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

Its town washed away centuries ago, this lonely tower by the sea tells the tale of a mermaid and a curse.

Invisible bridge parts the waters, invoking biblical images and preserving the ominous feel of an ancient moat.

Scale model of St. Peter's Cathedral (Rome) in the middle of a small Dutch town.

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

Inspired by "The Starry Night" this Dutch bike path turns into a glowing work of art each night.