A historic freight system that found the true gold rush is in tourism.

The ruins of this Alaska gold mine form a gorgeous ghost town.

This frozen tunnel in central Alaska is both an engineering feat and a valuable climate classroom.

Horrifically creative torture devices and shame punishments line the walls of this chilling museum.

The prototype for all Nazi concentration camps.

The fairy tale castle of the "fairy-tale king."

The footprint of a frustrated devil in Munich's Cathedral.

Go surfing on this urban wave, "hacked" by local surfers.

These bronze pamphlets remember a remarkable group of Germans who fearlessly opposed the Nazis in the very center of their power.

Golden cobblestones remember a time when this small alley was used to avoid having to give a Nazi salute.

The patron saint of spinsters grasps a container of dried blood.

An easily overlooked stretch of ornate window fronts and gaslight lamps that could be right from the pages of Dickens.

Hidden in one of New York's oldest subway stations is the final remnant of the site of the bizarre Shakespeare Riots.

A remarkable time capsule of American manufacturing deep in Maryland coal country.

Under a glass sidewalk lie the remains of some of Manhattan's oldest buildings.