This volcanic plug boasts the longest recorded history of any Scottish stronghold.

There's a crumbling old mansion inside the Smithsonian National Zoo.

The beloved statue at the National Academy of Sciences is oh so inviting to sit on.

A cavernous three-story, 43,800-square-foot basement that was forgotten about for 60 years.

A historic neighborhood church is reborn as a psychedelic arts collective.

Franciscan monks created a facsimile of the Holy Land for North Americans who couldn’t afford the trip overseas.

Nineteen ancient rock-cut Buddhist caves can be found on the outskirts of Mumbai.

The only Chinese temple in Mumbai.

In Mumbai, a bright blue synagogue is the largest one for the Baghdadi Jewish community in Asia.

A Zoroastrian funerary tower where excarnation rituals are carried out is threatened by the area's dwindling vulture population.

The place of worship for Zoroastrians, Mumbai's Parsi fire temples use fire and ash for purification.

It's a mystery how these curious columns wound up in an Edinburgh suburb.

The colorful stairs are made with marble from the world's major quarries.

Sprawled across the Great Hall ceiling are various constellations and images relating to the zodiac.

A beautiful Greco-Roman structure houses a well once believed to have healing powers.

A secret garden in a picturesque Edinburgh village has inspired artists for centuries.

Near the former site of numerous witch burnings, this lavish Edinburgh mainstay pays homage to Scotland's brutal history.

Tiny effigies of the victims of Edinburgh's famous Anatomy Murders.

This beautiful system of tunnels built into natural rock serves as a centuries old plumbing system.

Iran's colorful terraces are a rare geological masterpiece.

Modern-day cave dwellers carve elaborate homes out of volcanic debris.

Hydraulic systems in an ancient underground Iranian city.

In this tiny Iranian town playing on the roof isn't just encouraged, it's the only place to go.

This little Vancouver shack is a temple to all things Hendrix.