This short bridge is the only thing connecting a tiny Irish island to the mainland.

Northern Ireland's Brobdingnagian stepping stones.

The world's only flying boat museum honors a small Irish village that sent 20th-century aviation to new heights.

The largest portal tomb in Europe has a capstone weighing around 150 tons.

A stunning Victorian abbey and walled garden on a lakefront.

These imposing walls and towers look more like the ruins of a fortress than a monastery.

You can see three Irish counties from this Neolithic hillside fort, once the seat of the Kingdom of Ailech.

Huge standing stones mark a site of megalithic mystery.

This single room has survived the centuries with almost no deterioration.

One of Ireland's most infamous prisons for rebels including men, women and children.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

The first declared National Monument in the United States.

Lone survivor from Custer's Last Stand forever preserved.

Dedicated to the history of the 1,000 nuclear missiles that once covered the Great Plains.

A cemetery housing wild west legends in South Dakota.

Bill Murray bowled three straight strikes here at Reno's "Taj Mahal of Tenpins."

L. Frank Baum wrote part of the "Wizard of Oz" series in this wooden Victorian beach resort.

In the Middle Ages, villagers would sound this stone trumpet to boost fertility and coax fish to shore.

Built on the remains of one the Incas’ most important gathering spots, this square keeps the spirit of a fallen empire alive.

It took 82 years and four different plaques to finally get the story right.

Situated on a sacred Inca site, this 16th-century cathedral took nearly 100 years to build.

This geometric feat is a testament to the Incas' mesmerizing architectural abilities.

Preserved Inca city and site of the last Inca stronghold against the Spanish conquistadors.

Some 2,000 carvings show this rare desert spring has been an oasis for travelers for over a thousand years.