After this historic church was destroyed by World War II bombing, its blackened shell was left standing as a monument.

This 17th-century "unicorn" was cobbled together from the skull of a rhinoceros, the legs of a mammoth, and the horn of a narwhal.

A mechanical clock built in 1914, with a rotation of 12 historical figures on its face.

A meow-velous tribute to a beloved street cat, made famous on the internet.

The ornate miniature mansions were built for Istanbul's feathered residents.

Dedicated to the outnumbered Finnish forces who pushed back Soviet forces during the conflict.

From morgue to urn, watch the whole process at this unusual educational attraction.

This handsomely carved wooden church is more than 800 years old.

The ruins of a military fortification sit atop this mountain.

A monument to peace, built by one man over the course of 25 years.

A heated sculpture pays tribute to an actor who loved hugs.

The only natural cave bath in all of Europe.

Two volcanic lakes in an enormous crater formed in a prehistoric eruption.

A limestone grotto where daylight filters in from below and turns the water a beautiful turquoise. Also home to a small underwater nativity scene.

This lakeside bunker complex in Mamerki, Poland, housed the Supreme Military Command of Nazi Germany during World War II.

This wooden mosque is one of the few remnants of medieval Poland's Muslim Tatar community in this deeply Catholic country.

Dedicated to the lives lost during a fatal stampede in the Nyamiha Station.

The burning of this 12th-century church kicked off a campaign of Norwegian Black Metal terror.

What was once an underground Nazi city is now Europe's largest bat reserve.

Epicurean and holy traditions converge in what may be the oldest restaurant in Europe.

A Jenga-style cylindrical tower of books that appears to go on forever.

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

A memorial to the beloved brown bear that served in the Polish army during World War II.

The spectacular and eerie moss-covered grave site of 19th-century Belgian merchant.