Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

This pun was simply waiting to come to life, and one defense contractor made it so.

This enormous World War II relic is one of the largest wooden structures in the world.

A sign at the end of the Santa Monica Pier marks the traditional end of the legendary American highway.

A second generation sun-powered marvel lights up the night.

This centerpiece of the Hollywood & Highland shopping center is a recreation of a long-lost movie set.

This little-known Revolutionary War fort is supposedly haunted by the ghosts of its past.

North America's oldest quarantine facility was built in response to Philadelphia's 1793 yellow fever outbreak.

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

This sculpture by artist Fritz Keonig survived the 9/11 attacks and now stands as a monument to the victims.

Where the four original members of the Ramones hung out and revolutionized punk rock.

The last living thing to come out of the rubble after 9/11 is now a symbol of hope and resilience.

The remnants of two World's Fairs are here, complete with a 12-story globe, a mini-Manhattan, and a UFO-shaped pavilion.

Yo, Adrian!

Hidden behind West Philadelphia rowhomes is a haven for migratory and local bird species both ordinary and rare.

America's first serial killer rests in anonymity.

Ant sculptures march up the side of what used to be an iconic spot in punk rock lore.

While most of the games in this arcade take quarters, that would have been a small fortune when they were made.

Oddly shaped rock formation, misassociated with a nearby utopian community.

This Virginia railway overpass is said to be haunted by a serial killer in a rabbit costume.

At this Denver landmark, the meals are compulsory, the sopapillas are complimentary, and the insanity is everywhere.

A technicolor place of worship for Elevationists.

The Denver airport is guarded by a 32-foot-tall sculpture of a demonic horse.

The remains of the dam that unleashed a 15-foot wall of water on Denver.