This colorful gate stands as an entrance to the walled city of Old San Juan.

Above Breckenridge, a destructive mining technique sits sunken in a small pond.

One of the largest wooden ships ever built is honored by a steel sculpture evoking her once-superlative scale.

Accessible only by boat, this centuries-old island fort never saw troops or combat.

Explore the dark underground corridors of this graffiti-covered former military fortification.

This lone tree and dramatic sandstone outcropping are so beloved by Michiganders they can be found on one of the state’s coins.

These dramatic cola-colored falls have appeared in a poem by Henry Wadsworth Longfellow and a song by Sufjan Stevens.

This lighthouse and shipwreck museum keep a torch burning for the memory of the SS Edmund Fitzgerald.

Amid rushing rapids, this small bit of land is an important First Nations site on border between Canada and the United States.

Beautiful scenery, history, science, and physics come together in this remnant of shipping lore.

Island where motor vehicles are banned -- home to the only carless highway in the United States.

The fifth-longest suspension bridge the world, connecting one Michigan peninsula to another.

Former self-sufficient mental institution now a planned community.

A crumbling mountain resort that looks like it was abandoned in an instant.

One of the few working locomotive roundhouses in the United States.

The 80-foot tire that looms over Michigan's I-94 was once a Ferris wheel in the New York World Fair.

Where the Model T was made and the assembly line was invented.

This empty Detroit high school was too expensive to maintain or destroy.

A Beaux-Arts triumph set to become Ford's innovation campus

This public baseball field is a beloved remainder from of one of the most historic stadiums in the country.

Abandoned concert venue legendary for its rock counterculture.

This Detroit ruin was once a gothic bastion of its community, but now it stands as a haunting ruin.

Berry Gordy Jr.'s old home was the original headquarters of Motown Record Corporation.

The birthplace of the Ford Model T is now a museum full of antique cars.