Vast network of air raid tunnels beneath Lombardy's capital.

A garden full of metal sculptures that celebrate the double bass.

The little-known final resting place of one of America's greatest writers.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

Nondescript elevator doors open to reveal a stunning, surreal world.

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.

A remnant from the golden age of aviation still in use today, Pan Am's Clipper service took off from this Art Deco gem.

A uniquely lettered street sign marks the corner where the iconic word game was invented.

This New York estate was designed to resemble a medieval Scottish castle.

A "Bugseum" dedicated to all things insect-related resides behind a pest control company.

A unusual sanctuary for abused and exotic animals in South Jersey.

How this Pine Barrens hill got its name is uncertain, but on a good day the view from the fire tower is crystal clear.

The site of one of history's most indelible and horrific tragedies.

Beautiful stained glass depictions of the history of human flight fill this surprising chapel.

This domed temple was built in a hidden cave mouth as a refuge for sinners seeking absolution.

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

There's a 12-foot-tall replica of the Washington Monument hidden under a manhole nearby.