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.

Frank Lloyd Wright's most iconic home dangles over a Pennsylvania waterfall.

A layered tribute to the work of mosaicist Isaiah Zagar.

A 90-year-old underground water reservoir offers a more industrial kind of tranquility.

This Annapolis home was built by one of the signers of the Declaration of Independence.

Captain John Smith thought these cliffs were amazing in 1608 but sharks thought so 20 million years before him.

Despite violent work crews and massive delays this abandoned canal tunnel was built to last into the modern day.

The remnants of a wooden-hulled fleet built and abandoned in WWI, now home to a thriving ecosystem.

This English-inspired Maryland garden is home to acres of opulent plant life including bushes shaped into an entire fox hunt.

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

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

Contains a wealth of information about the first exploration and later use of the Green and Colorado Rivers.

At Washington's Dulles Airport is a satellite museum (no pun intended) with three quarters of a million square feet of aircraft history.

The taxidermy remains of the most popular pony in children's literature.

A sacred site for Native Americans surveyed by George Washington and owned by both King George III and Thomas Jefferson.

The remains of a failed attempt at medieval nerdery are hidden deep in the woods of Virginia.

Giant busts of 42 U.S. presidents are sitting in a field in Virginia.

The shelves in the back of this thrift store are devoted to saving, not selling, retro tech.

A benevolent, 16-foot-tall river dragon lives on a suburban lawn.

An intricately designed junk art house with four extravagant junk art cars hidden in the suburbs.

An old pay phone rewired to play local bird calls and songs at the press of a button.

A historic Maryland home that once belonged to a man who has been called "the most insignificant" U.S. Supreme Court justice.

A remote horde of architectural treasures fit for Indiana Jones.

Eighteen miniature death-scene dioramas.