Artistic tombs, monuments, and a beautiful "Hall of Fame" lurk inside this cemetery.

Small on the outside, big on the inside, this church is an astonishing act of visual deception.

Two very green residential towers cleaning the air in one of Europe's most polluted cities.

An ossuary built in 1210 to collect bones from the Ospedale Maggiore of Milan.

Ruins of a late 1950s Polish ski jump ramp in the middle of the city.

This extensive collection covers thousands of years of Polish military history.

A delightful museum entirely dedicated to the tiny homes of dolls.

The Polish capital has had a deep connection to its guardian mermaid for almost a millennium now.

The final resting place of more than 200,000 people, this is one of the largest cemeteries in Europe.

This hidden collection of everyday objects illustrates life within communist Poland.

A national collection of Communist-era musical posters.

A menacing statue of this mythical creature can be seen at the legendary site of the monster's lair.

A 20th-century picture show in 3-D.

A hidden art gallery in an abandoned Warsaw fort.

A program of Communist glamour in post-Stalin Poland is preserved in this colorful museum.

The best place in the world to buy tinned fish.

An early Portuguese serial killer's head is alarmingly well preserved in a jar at the University of Lisbon.

This once-forgotten oasis in the middle of Lisbon was first created over a century ago quite by accident.

Ring the bell to enter a bar that looks equal parts museum and old curiosity shop.

This charming candle shop has been in business since 1789.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

Nine centuries-old fortresses guard the walls of this medieval Romanian city.

This hauntingly beautiful cemetery outside a medieval citadel is full of winding paths and ivy-covered graves.