Visitors to this library are in for a real-world education in modernist architecture.

The farthest you can be in the contiguous U.S. from a McDonald's location.

Population: 1.

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

An earthwork sculpture built by Robert Smithson in the Great Salt Lake only reemerges during drought.

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

The first declared National Monument in the United States.

The only road through the heart of Glacier National Park.

An architect's childhood fantasy treehouse made real.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

An entire town preserved as a historic landmark.

The final resting place of the poets Shelley and Keats.

A Nesting Doll of Churches.

This former Roman Catholic Church still contains the embalmed hearts and organs of 22 popes.

Breathtaking and huge 430 year old maps of Italy.

Renaissance hospital featuring a rotating door into which unwanted babies were dropped.

This bridge is the first to be made entirely from iron, but designed like it was still made of wood.

Ancient paintings known as the "Sistine Chapel of Cave Art."

A theatre built to house the rowdy Oxford graduation ceremonies became the stage for a debate about God's existence.

In memory of The Blur Building, the temporary exhibition pavilion of vaporous nothingness.

Famously misunderstood wonder of the ancient world

A cluttered and astounding collection of antiquities and curiosities.

Scattered throughout London are ancient remnants of the city's former bounding wall.

A vast overgrown cemetery, once known as one of London's "Magnificent Seven."