This collection of odd proofs of concept is like taking a walk through the imagination of a Victorian engineer.

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

These tourist trap caverns are said to be the former home of a legendary Pennsylvania Hermit.

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

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

A pre-Industrial Age iron furnace and the site of a nearly-forgotten piece of Black history.

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

The site where Poe "in great distress, and ... in need of immediate assistance" likely died.

A Civil War Museum with some notable medical antiques.

A priceless collection of the Nation's cryptologic history.

A traveling postal dog covered 48 states and more than 140,000 miles, and he lives on as taxidermy, patched up with a rabbit's foot and a pig's ear.

The most decorated dog of World War I is preserved in the Smithsonian.

Home to items never before seen by the public.

The site of the climactic scene from the classic horror film is now a historic landmark.

A Civil War fort in the middle of Washington, D.C. has been swallowed by a forest.

The tallest The Church of Jesus Christ of Latter-day Saints temple in the world soars above the Beltway.

The final resting place of the tragic king and queen of the Jazz Age is tucked away in a small Maryland graveyard.