This World War II bunker now survives as a documentation of the Nazi regime and war crimes.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.

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

This small town in the Netherlands has no roads but instead, miles of canals and over 100 bridges.

A beautiful collection of architectural ornaments rescued from demolished New York City buildings.

The world's only museum devoted to the wonders of fluorescence.

Haven for steampunks.

An easy to overlook storefront hides some of the most authentic and regionally diverse Chinese food in New York.

An annual extravaganza of Broadway theater memorabilia.

The crown jewel of the Queens Museum is a nearly 10,000-square-foot architectural model of the city originally built for the 1964 World's Fair.

One of the most enjoyable bits of history at Coney Island and “the most romantic ride in the world.”

The world's oldest hologram gallery and the labyrinthine laser laboratory of a holography pioneer.

A three-story copper skybridge connects two Manhattan buildings with Art Deco luxury.

Hidden in Central Park's Ramble is a troublesome cave buried just beneath the surface.

A hip bar decorated with walls of golden skulls.

Order scoops of pandan, lychee, and black sesame at this family-run institution.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

Try not to get slimed in Tribeca.

Bacteria and algae give the salty water its bubblegum hue.

This impressive collection of skulls and bones was gathered by an ex-zookeeper who took advantage of a pig plague.

This Belgian theme park began as a refuge for bored church children and was closed down when a boy lost an arm.

A huge old mansion full of thousands of toys, each there to be used and played with.

This recently restored crypt was once plagued by liquefying coffins and exploding caskets.