The secret city built by the Manhattan Project.

This bridge over D.C.'s Rock Creek Park is sometimes called the "Buffalo Bridge" because of its four buffalo sculptures, which were cast from a single piece of bronze.

Behind an abandoned storefront is an example of pioneering 1930s gas station architecture.

Also known as the Founding Church of Scientology.

A brass and marble scale model of the solar system embedded in the concrete.

Cold War intelligence agents monitored communist embassies from an attic in a former pigeon coop.

The rooster who crossed the road lives on forever in Takoma Park, Maryland.

Montmartre's sole surviving windmill became an iconic landmark for 19th-century painters, artists, and bohemians.

The last standing piece of a famous Honolulu landmark.

An ode to one of the first concerts broadcast via satellite.

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

Take in a sweeping views of Guanajuato—and save yourself a hike up a steep hill—on this funicular.

The oldest remaining frame residence in Minneapolis.

This old residential building was once the largest flour mill in the world.

The only arched bridge made of stone on the entire Mississippi River.

This kaleidoscopic mural shows Bob Dylan throughout his transition from young troubadour to Nobel laureate.

One of two giant blue cockerel statues erected with an intentional double meaning.

A toweringly silly piece of modern art has been delighting locals since the 1980s.

A bronze statue on a downtown corner honors Minneapolis's favorite career gal.

An ancient capital city that dates back 3,000 years old and harbors many surprises.

The Dead Sea Scrolls were discovered in the ruins of this ancient monastic community.

This daunting 1st century fortress was purportedly the site of one of the most dramatic revolts of the Jewish-Roman wars.

These numerous Israeli caves were dug out over hundreds years for reasons ranging from hideouts to burial sites.

Developed by focused shutterbugs, this museum exposes visitors to more than 6,000 different cameras.