Two small markers remember the Alamo's feline protectors.

An ivy-covered arch bridge dedicated to Tejano music singer and legend Rosita Fernandez.

This town is home to the world’s largest arch constructed entirely of elk antlers.

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

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

The enormous 250-room Vanderbilt mansion conceals hidden doors and secret passageways.

This advertisement for talcum powder was painted on the rock face and has since defied removal.

A recreation of the doomed ocean liner in the middle of the Smoky Mountains.

The time thousands of bags of chips washed ashore in the Outer Banks is memorialized in a local museum.

So many migrating birds roost on the bridge, it has a special summer speed limit.

This shifting North Carolina sand dune is an odd little desert surrounded by oceanic forest life.

Practice your Dirty Dancing lifts in the manmade lake where Johnny Castle himself did.

The only known Futuro house in North Carolina sits along a stretch of desolate highway on the Outer Banks.  .

This high point in the Great Smoky Mountains is said to be home to the chief of all bears.

This geothermal hot spring hides beneath a slowly growing mineral dome.

This mysterious structure by the Washington Monument is a flood barrier designed to protect the White House against rising waters.

An overlooked memorial honoring the local Washington residents who died in World War I.

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

While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

A tiny monument to the unsuccessful attempt by Thomas Jefferson to place the prime meridian in Washington.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

An overlooked oasis of quiet on the grounds of Washington's monumental basilica.

The "lovely red Vega" of the legendary record-settling pilot.

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