This bleach-white graveyard overlooking the ocean is accessed through a tunnel.

Legend tells how a Spanish soldier disappeared from this isolated sentry box without a trace.

The world's brightest bioluminescent bay.

On this Puerto Rican island, many abandoned naval ammunition bunkers sit open while a few have been padlocked by locals as personal storage.

"...I guess that was your accomplice in the wood chipper?"

Millions of years of erosion created the feature for which this rock formation is aptly named.

The site of Paul Revere's historic two lantern warning.

Statue commemorating the use of ether in anesthesia.

American revolutionaries and British soldiers alike are buried here in the fourth-ever cemetery in Boston.

The final resting place of the first documented Chinese person in the United States lies in a Boston cemetery.

This bronze sculpture was inspired by a photograph of Martin Luther King Jr. and his wife embracing after he won the Nobel Peace Prize.

A hidden courtyard houses early 20th-century plaster masterpieces.

The world's largest outdoor organ is played weekly by one of just two civic organists in the U.S.

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

One of the oldest scientific gardens in Britain, containing more than 13,302 plant species in its core collection.

Since its original beginnings as a weather observatory mountaintop, this facility played an instrumental role in gathering atmospheric data for almost 100 years.

Few other hotels can rival the grandeur of the Castle in the Rockies.

A Victorian garden in a harsh climate at the border of the prairies and foothills of the Canadian Rockies.

A brick-paved former section of the historic coast-to-coast highway.

These experimental weapons brought World War II to Nebraska as well as 26 other U.S. states.

This First Nations monument is a peaceful spot with vast views of the Calgary prairie.

Decorated by local artists, the city's utility boxes have become three-dimensional canvases.

With its webbed walls and bright red coloring, Calgary's iconic bridge looks like a finger trap puzzle stretched across the river.

Formerly known as National D-Day Museum, this collection commemorates the battles of Normandy and WWII.