The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

This palatial botanical garden is home to one of the largest pipe organs ever installed in a private residence, and a piece of Wood's cycad.

These lush botanical gardens employ the most purrfect pest control force.

A blend of art, antiquities, and Americana fill this museum, surrounded by whimsical, enchanting gardens.

A priceless collection of the Nation's cryptologic history.

Crammed into a Baltimore row house is an oddities shop that sells everything from skulls to dead insects.

This bug-eyed water wheel uses the power of the Sun to clean up Baltimore Harbor.

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

A statue of the English poet for whom this Delaware town is named is ritually dressed in seasonally appropriate clothing.

These old doors are covered in the signatures of Rehoboth Beach artists dating back to the 1930s.

A grotesque Fiji merman dwells within this traditional Dutch-style building.

The historic home still shows the scars from a little run-in with the British in 1813.

Enchanting gardens surround a derelict mansion, all hidden in plain sight behind a stone wall.

A scenic fort on the harbor protected Philadelphia from an attack that never came.