This isn't your average roadway—it's actually a National Park and a transportation pioneer.

An organ located deep within a cave, whose "pipes" are the geological features of the cave itself.

Once home to seven different roller coasters, Glen Echo has undergone many transformations since its founding in 1891.

The land is home to swimming ponies and a legendary 18th-century treasure.

A well-preserved example of an early industrial operation in the northeastern United States.

A converted hangar displays dozens of helicopters, from a famous 1943 rescue chopper to several autogyros.

This dramatic rail curve was once the target of a failed Nazi attack.

America's first serial killer rests in anonymity.

The world's tallest doric column is this Ohio monument to a naval victory in the War of 1812.

Mausoleums, astronomy, and animatronic dinosaurs at this memorial to an assassinated American president.

The home made famous by the 1983 holiday classic is now a perfectly preserved shrine to the movie.

There's more contention than one might expect from cherry pie pans.

Step into a pastel time capsule where candy is truly dandy.

This small park features a monumental fountain wall, providing a great photo opportunity in the middle of Houston.

A burial ground for workers at one of Hawai'i's largest sugarcane producers that laid buried for decades.

This impressive Boston holy house is the American mecca for Christian scientists.

Mrs. Mallard and her brood are a beloved fixture in Boston Public Garden.

The Boston square dedicated to the dark poet who was born nearby.

The place where Samuel "Slater the Traitor" brought the Industrial Revolution to America.

A work of art that pays homage to a Victorian timepiece in Providence.

Ironically this massive termite is the mascot for a company that is acclaimed for killing his kind.

A relatively obscure antihero from the Marvel Comics universe adorns a wall inside Iceland's main airport.

Three columns of volcanic rock shoot out of the ocean.

Lovingly nick-named the "Brick Dick" this municipal tower was winner of the World's Most Phallic Building Contest.