A remnant of Korea's colonial past lies forgotten in a hip neighborhood in Seoul.

Building this tragically pointless stone barrier cost the lives of the prisoners made to build it.

Since the 1700s, this old barrel has acted as a post box that relies on the kindness of travelers.

Quito's historic, main square dates back to the 16th century.

One street divides a single town that stands in two U.S. states.

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.

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

The trials and tribulations of marking Poe's grave.

Sitting in the arguable birthplace of the Wild West, this museum holds the largest collection of bronco busting bric-a-brac in the world.

World's smallest skyscraper, the product of a remarkable con.

Final resting place of Geronimo, Quanah Parker, and the first atomic gun ever fired.

American bison herd descending directly from a Bronx Zoo breeding program that saved the species from extinction.

A sculpture made of 10 Cadillacs as a monument to the "Golden Age" of the American automobile.

So many migrating birds roost on the bridge, it has a special summer speed limit.

Every week, a festive public jam session breaks out in downtown Asheville.

The North Carolina grounds are leased in perpetuity to the British Commonwealth for as long as the WWII sailors are buried there.

This 5-by-6-foot wooden hut is the smallest historic post office in the U.S.

This too-low North Carolina railroad trestle is still a notorious big rig executioner.

This shifting North Carolina sand dune is an odd little desert surrounded by oceanic forest life.

The world's largest vertical wind tunnel.

A forgotten sea village stands silent after hurricanes deemed it obsolete.

The enormous 250-room Vanderbilt mansion conceals hidden doors and secret passageways.

The U.S. Supreme Court's secret Cold War relocation facility in the mountains of North Carolina.