In its day this historic fort held 100 cannons pointed in almost every direction to protect New York.

Lie in a hammock where George Washington stood.

Try not to get slimed in Tribeca.

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

The original toys that inspired the beloved children's stories are on display at the New York Public Library.

A crumbling hospital from the 1850s on Roosevelt Island.

The first museum in the United States dedicated entirely to posters.

Hidden in plain sight on a pair of Manhattan subway tunnels are a pair of public instruments that sing to each other.

Everyone from Mark Twain to Teddy Roosevelt has a pipe hanging from the walls of this historic chophouse.

The smallest island in Manhattan is a manmade landfill dominated by a Buddhist peace arch.

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

The first piece of public art dedicated to LGBT rights.

New York City's smallest piece of private property.

One of the largest helium balloons in the U.S. is a 112-foot ginormous orange.

This unlicensed collection of fast-food memorabilia sits on the site of the first ever McDonald's restaurant.

The liveliest ghost town in the state.

This impressive tunnel was dug entirely by hand over the course of 36 years.

Smooth basaltic rocks tell a tale of ancient glacial waterfalls.

The tragedy of the Japanese internment camps is remembered here by a stark "Soul Consoling Tower."

A charming desert roadside bakery that produces 10 times more bread daily than it has residents in its town.

Aqueducts have dramatically changed this old lake, now home to tufa towers and its very own species of tiny brine shrimp.

Handmade treasures from around the world.

A unique market that brings together various goods and cultures.

California's own medieval Italian castle, authentic down to the 300-year-old iron maiden in the dungeon.