Like Mars, but much closer.

Mysterious rocks that ring musically when struck.

A precariously balanced rock perches on the edge of a cliff created tens of thousands of years ago by glacial erosion.

Once the future of underwater combat, this old sub is now open for visitors to muck around in.

The internal railway of one of the biggest steel plants in America has been transformed into a linear park with unique industrial views.

Once America's tallest structure, now a Baltimore landmark.

Thousands of tiny squares in different colors make up this piece of street art.

Equal parts record-breaking temple to consumerism and bizarre fun park, it's more than you think it is...

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

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

Detroit’s Eastern Market has been transformed into an outdoor museum with colorful murals that address social issues and symbolize the city.

This former industrial site has transformed into a community sculpture garden that hosts monthly Full Moon parties.

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

One of the world's premier laboratories for hydraulic engineering research takes full advantage of the water's power.

No one's quite sure where this quirky university tradition originated.

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

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

This iconic water tower and failed bandstand is open for panoramic views once a year.

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

When flour explodes, it's not a pretty sight.

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

A mysterious monument meant to be a guide into "an Age of Reason" was destroyed after an apparent bombing.

Follow the steps, and this roadside artwork will teach you how to dance.

Once decrepit and slated for demolition, now one of the longest pedestrian bridges in the world.