A completely round house designed for the Atomic Age.

This little-known Revolutionary War fort is supposedly haunted by the ghosts of its past.

America's first serial killer rests in anonymity.

The final resting place of one of the United States's greatest poets.

This giant disembodied horse head seems to balance impossibly on its nose.

Ant sculptures march up the side of what used to be an iconic spot in punk rock lore.

America's smallest national park site is the former residence of exiled Polish national hero Thaddeus Kosciuszko.

The oldest of only three existing statues of the great novelist stands in a city he did not care for.

This little-known collection holds everything from "Dracula" notes, to the manuscript of "Ulysses," to the forged works of Shakespeare.

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

The sounds of the world's largest fully functioning pipe organ dazzle shoppers at a Philadelphia Macy's.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

This beloved marketplace mascot poops money and grants good luck.

Yo, Adrian!

Tour the dark and beloved poet's former cobwebbed basement, which may have inspired "The Black Cat."

Frank Lloyd Wright built this suburban synagogue late in life, but it stands among his most iconic masterpieces.

Designed by Horace Trumbauer in 1893, this Gothic-style castle is now a home for academics.

This family of wooden moose statues have become local celebrities in their hometown.

A replica of a famous Greek statue adorns the front of the unusual home of architect and alchemist Humberto Pittamiglio.

An Argentinian businessman facing terminal cancer built this whimsical medieval village using salvaged materials.

The narrowest house in Buenos Aires is less than 10 feet wide.

Museum housed in underground tunnels that date back to Buenos Aires's earliest settlements.

A gateway to a mysterious network of underground tunnels.

A tower devoted to — and modeled after — the Divine Comedy.