A volcanic core jutting above the plain between the Snake and Boise Rivers, a marker identifies the reference point for all U.S. Government Surveys in Idaho.

A journey begins with a single step, and for many, the road-trip of a lifetime started at this Chicago intersection.

In 1857, the Mardi Gras parade tradition began at this intersection.

A unique post-modern public space in the middle of the Warehouse District in New Orleans.

On the side of a Virginia highway, a collection of monuments commemorates an 18th-century trek through the Blue Ridge Mountains.

As the glaciers retreated out of northern Wisconsin, this unique natural wonder was crafted.

This park harkens back to frontier life in Wisconsin.

The tragic death of 19-year-old Mabel Tainter in 1886 led to the construction of this unique Victorian-era theater in the northern woods of Wisconsin.

A sprawling maze of used books piled from floor to ceiling.

The remains of the man who founded Pennsylvania lie in an unassuming grave in the English countryside.

This floating sculpture of ice is a poignant reminder of nature's power.

Latvia's symbolic mountain-shaped national library is home to millions of cultural tomes.