A mysteriously abandoned campsite in San Angelo State Park.

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

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

This stunning, out-of-the-way Croatian monument commemorates a community's uprising against occupying fascist forces.

A full figure 4th century incorruptible saint lies in a glass coffin in Croatia.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

A small self-proclaimed micro-state located on a piece of disputed territory between Croatia and Serbia, near Liberland.

A self-proclaimed libertarian micro-state on a tiny bit of disputed territory between Serbia and Croatia.

Elaborate stone houses constructed from the ruins of war.

The railway carts travelers to central Athens's highest peak, which offers stunning vistas of the city.

A historic building houses one of the most important archaeological institutes in Europe.

These caves secretly held national treasures during World War II.

This building displays the scars of the “Dekemvriana,” a dark time in modern Greek history.

A grotesque collection of wax limbs depicting the symptoms of venereal disease.

Dubbed "Wistom" by locals, this abandoned factory is an urban explorer's dream.

The giant metal fruit was once the symbol of a large farm.

A huge wooden clock that is so beautiful its creator was forcibly blinded.

Real bones which are said to have belonged to a Polish dragon.

A striking public sculpture representing the period of martial law in Communist Poland.

The silly symbol for an underground protest group is now scattered around the city.

Countless stories attempt to explain Poland's mysterious J-shaped trees.

The manor house where the Polish composer spent childhood summer holidays is now a museum and concert hall.

In the center of Wrocław's old meat market stands a somber tribute to the city's livestock.

An artificial date palm stands as a memorial to Warsaw's Jewish community.