One of the last few places in Manhattan that employed a pneumatic systemic keeps it on display.

One of Madrid's oldest trees, with a long and colorful history, resides in El Retiro Park.

This evocative New Jersey statue memoralizes the Polish victims of a Soviet massacre.

On the Hudson resides one of the largest clocks in the world.

The site of a fallen tree that protected Americans from British forces during the American Revolution.

An eerie diorama that captures the majestic nature of a few prehistoric-looking beasts.

This elaborate tunnel is the first structure composed of cast concrete in the United States.

Once a dumping spot, now a park with a kayak launch.

This city park was once a lookout point for George Washington’s army during the Battle of Brooklyn in 1776.

This anonymous businessman sculpted in bronze became an enduring memorial after 9/11, and had been mistaken by rescue workers for a survivor in the rubble.

There are owls with glowing eyes in Herald Square.

Cheap pizza and all of your naughty bedroom needs housed in a stunning example of Art Nouveau architecture.

One of the few remaining American elm trees in New York’s Tompkins Square Park was the birthplace of a new religion.

If it hadn't been caught in time, a flaw in the design of this Manhattan skyscraper could have led to its collapse.

A set of seven houses, each built in a style that represents a European country.

This tree was grafted from the actual tree that led Isaac Newton to ponder the theory of gravity.

This home designed for chocolate magnate Antoni Amatller is an exquisite treasure-box of Catalan Modernism.

An automaton perched above an classic clock and watch store

The remains of this 2nd-century Roman temple are incorporated into a modern building.

A massive marble foot is tucked away in a small alley near the Pantheon.

A whimsical European-style chateau that calls the coast of Chile home.

You can spend the night in Dr. Frank-N-Furter's castle.

Numberless clock creates a meal of time for the dreaded, insectile Chronophage.

Once one of the largest rooms full of books in the world, this bookstore basement is still a treat for bibliophiles.