A Pythagorean funhouse that tries, successfully, to prove that math is the coolest thing ever.

A hands-on traveling collection of the innovative devices of yesteryear.

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

The feral felines of Roosevelt Island have a small army of allies and an abandoned hospital all to themselves.

This lower Manhattan bar is set up in an old bank vault that rests beneath a skyscraper that hides even more historic splendor.

New York's oldest magic store.

A miniature rainforest is growing inside of a Midtown Manhattan office building.

The oldest family-run luncheonette in New York, last renovated in 1948, still serves food and drinks the old-fashioned way.

This abandoned subway station beneath the Waldorf-Astoria hotel is allegedly used to secretly transport presidents.

This beautiful building in the heart of Manhattan's Financial District was empty for decades.

A treasure trove of artifacts, books, and artwork from the "golden age" of exploration.

A crumbling hospital from the 1850s on Roosevelt Island.

La Monte Young and Marian Zazeela's "Dream House" will immerse you in an ever changing world of sound and light.

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

Complex aquaponics systems allow fish and plants to grow in harmony.

Amateur taxidermy museum known for its large collection of white squirrels.

This park harkens back to frontier life in Wisconsin.

The tragic death of 19-year-old Mabel Tainter in 1886 led to the construction of this unique Victorian-era theater in the northern woods of Wisconsin.

The site of an ancient Mississippian settlement that appears to have flourished during the 10th to 13th centuries.

This storied music venue was once a tavern that housed an Italian Anarchist book club and prohibition parties; today it's a community space for artists and musicians.

As the glaciers retreated out of northern Wisconsin, this unique natural wonder was crafted.

A renowned Civil War veteran, this Bald eagle now presides over the Wisconsin State Assembly.

This lakefront cottage was crafted in the 1800s and was once a sanitorium.

The building was originally a gas station built to resemble a Japanese tea house.