An old airplane engine forms an unusual cairn atop this Moroccan peak.

Freddie Mercury's childhood home is now a monument to the iconic Queen rockstar.

In Zanzibar, a historic 19th-century palace is a reminder of the world's shortest war.

This sacred, circular cave is lined with pools so clear and still that it's hard to tell where the water begins.

Mrs. Mallard and her brood are a beloved fixture in Boston Public Garden.

Berthed at the Charlestown Navy Yard in Boston, "Old Ironsides" is the oldest commissioned warship still afloat.

This monument on Breed's Hill proves that one of the most famous battles of the Revolutionary War is misnamed.

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

Stolen goods adorn the organ at Old North Church.

Dedicated to nine marines from Massachusetts who perished during the Beirut bombings.

An easy-to-miss garden in Boston's North End honors the mother of JFK and others who lost children in WWII.

An out-of-the-way wildlife haven with a rich and storied past of harboring thousands of fugitive slaves, or "Maroons" during the mid 1800s.

Outdoor exhibits explore the contributions of European, African, and indigenous peoples to American frontier culture.

A 19th-century relic of timekeeping.

For decades, Puerta del Sol has been illuminated by a giant, guitar-wielding bottle of sherry.

An imperial fortress city that incorporated cultural elements from the entire Mughal empire, only to be abandoned the year it was finished.

Also known as the "Red Taj Mahal."

This 18th-century complex has served as a mosque, mausoleum, and one of the largest caravanserais in India.

This strategically-placed fountain creates the magnificent illusion of mustangs galloping across a river.

A few times a day, you can see an animatronic cowboy shoot-out.

The beautiful 16th-century stepwell lies in the shadow of a famous fortress.

This opulent 16th-century Maharaja’s palace is a unique mix of Hindu and Muslim designs.

More than half of this Indian palace is drowned but it looks all the more spectacular for it.

Ornate, dome-topped cenotaphs fill this royal crematorium.