A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

This striking royal residence is the largest Renaissance-style castle in Scandinavia.

Climb to the top of its spiral spire for spectacular views of Copenhagen.

The oldest amusement park in the world has been providing a nice spot to have some fun since the 1500s.

The northernmost point in Denmark is a turbulent sandbar created by two clashing seas.

The old observatory in Copenhagen has a spiral corridor used as a racetrack.

Beneath Denmark's Højbro bridge, a bronze merman and his seven sons forever mourn for the mother and wife who left them for land.

Old Danish castle immortalized in Shakespeare's Hamlet.

Pre-Nazi swastikas adorn the sculpted pachyderms flanking this brewhouse portal.

An enormous effigy of the goddess of compassion hides within the sanctuary.

A labyrinth of clothing, electronics, and other counterfeit items.

The powerful party began with a secret meeting in this shikumen in 1921.

Two nearly identical Chinese pagodas stand side by side, along with ancient stone relics.

A tidal bore with its own festival.

This under-visited temple is nestled within one of Shanghai's traditional shikumen-style residential blocks.

This temple located on a vertical drop of a rocky mountain houses relics from the Song Dynasty.

A wall within the institution displays the names of 13,000 Jews who took refuge in the city during World War II.

A giant scale model giving a sneak peek at what urban planners see for Shanghai by 2020.

This former textile district now is now a thriving center for contemporary Chinese art.

China's most famous acrobatics act.

An out-of-place slice of France, smack in the middle of Shanghai.

A son-and-daughter meat market, hawked by mom and dad.

This smaller cousin of the Forbidden City has gone from ancestral sacrifice to tourist's whispers.

The once highest point in China blends symbolic design with a kick of adrenaline.