This concrete ship has had four careers - World War I tanker, floating amusement park, fishing pier, and artificial reef.

When California condors were hovering on the brink of extinction, this recovery program was charged with helping the birds thrive again.

A giant, Gilded Age mansion that once belonged to the beer baron of Milwaukee.

The only Chicago bridgehouse open to the public contains a museum devoted to the Chicago River.

Partially submerged Buddha heads freckle Chicago’s neighborhoods.

A park full of giant teddy bear statues was an anonymous gift to its host city

Opened in 1956, the first modern indoor shopping mall in the world was inspired by the shopping arcades found in European cities.

A winged-helmed, sword-brandishing tribute to German Americans.

This early 20th-century rural drinking fountain provides water for both horses and humans.

This bright yellow building is packed with sweet treats from all around the world, from chocolate-covered crickets to whoopie pies.

Beneath unsuspecting visitors feet, a capsule containing pieces of America’s civil rights history.

A computer bug so primitive it was an actual insect.

Born a slave on the Arlington estate, Parks dug the first graves at Arlington National Cemetery, and was buried there, too.

A cavernous three-story, 43,800-square-foot basement that was forgotten about for 60 years.

The innocent intentions of this monument are somewhat lost in the sculpture's muscled imagery.

Purdue students would lean over this iron fence to skirt campus rules against smoking and courting.

The world's largest anatomically accurate brain sculpture.

On the campus of Franklin College you can get a Benjamin Franklin twofer.

This hidden stream beneath Indianapolis makes an appearance in the best-selling novel "Underground Airlines."

This whimsical park encourages its visitors and wildlife to roam on and around the various works of art.

Nature and art meet in this curvy creation

The famous red-and-white Campbell's Soup label beckons hungry passersby in Ohio.

This quirky UFO-shaped curiosity is often mistaken for the airport’s control tower.

Once strictly off-limits, this lower level housing curious and priceless vehicles of the Petersen Automotive Museum is now open to the public.