Arrr! The most authentic collection of pirate artifacts in the world... matey.

In this case, 'zero' marks the spot where the iconic Old Spanish Trail ends.

The walls of America's oldest masonry fort famously "swallowed" cannonballs.

The only Florida state park with publicly accessible caves.

One of the world’s largest and deepest freshwater springs, where mastodons once roamed.

World's largest magnetic research facility.

This state park was once an important Native American cermonial center.

A modernist landscape of water and sci-fi concrete.

San Francisco's newly reopened hands-on science museum.

A replica of the first public theater built in California.

Surrounded by a hundred mile radius of billboards, Little America is a roadside attraction whose primary appeal is hospitality.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

This prehistoric sinkhole lured exclusively male mammoths to their death, much to the delight of science.

Other-worldly rock formations and ancient fossils abound in this unique stretch of Nebraska badlands.

This erect, phallic geological spire wasn't always named so domestically.

An experimental, automotive replica of Stonehenge.

A devilishly named gorge that was a sign of salvation for many pioneers.

This Yellowstone geyser may not shoot as high as the nearby Old Faithful, but it erupts for considerably longer.

See the computer’s history revealed over the course of 20,000 years.

The old fire tower is one of the last of its kind in the United States.

The world's largest Holstein cow.

The world's tallest turtle riding the world's largest snowmobile.

A rim-made reptile in North Dakota.

This replica of an 8th century burial ship actually sailed to Norway before returning home to Minnesota.