Largest Roman Catholic church in North America.

A monument in Washington D.C. marks the spot from which all other roads were supposed to stem.

The monument's pointy aluminum tip has been melted down by repeated lightning strikes.

Look closely and you’ll notice that the color changes a third of the way up the tower.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

A 1,100-ton train fell through the floor in 1953. Workers got it patched up in just 72 hours.

The romance of early commercial flight still fills this Art Deco destination.

This extraordinary Depression-era expenditure was modeled after a postcard of a Mediterranean hotel.

Funded by John D. Rockefeller, this is one of the earliest, and most beautiful, shopping arcades in America.

This steamer is known as "The ship that built Cleveland."

The world's tallest doric column is this Ohio monument to a naval victory in the War of 1812.

An exotic wildlife habitat right off The Strip.

What was meant to be a temporary exhibit is now a permanent fixture at the St. Louis Zoo filled with beautiful birds.

The Old Courthouse takes visitors on a captivating trip through St. Louis' timeline.

Once one of the world's great cities, Cahokia was a place of religious worship, trade and mass human sacrifice before being mysteriously abandoned.

When you visit his grave, be sure to rub the Great Emancipator's nose for good luck.

Sparkling, calcite-covered skeletons of children who may have been sacrificed to appease an angry god.

These roaring primates were considered a divine creature in the cosmology of the Maya.

A massive underwater sinkhole made famous by Jacques Cousteau.

Monkeys inhabit the lush forest surrounding ancient Mayan ruins once considered sacred.

This portion of a lovely Belize beach is infested with (harmless) sharks and rays.

Deep in the Guatemalan jungle stands an ancient pyramid that once marked the reign of a king.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.