Natural sonic phenomenon comes with a grisly legend of murder and blood.

This failed condo development was reborn as a street art hub.

An 18th-century Spanish watchtower made entirely of seashell and concrete.

Erotic art covers the walls of the largest ancient pleasure palace.

The oldest burial ground in the city, final resting place of city founders, Ohlone natives and murderers alike.

An historic and oft-filmed spot for musclebound iron pumpers on the Pacific coast.

A gothic church spire sits atop this skyscraper, the tallest church in the world.

The largest collection of two headed animals in the world.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

Beautiful Austrian natural history museum with carved ceilings and row after row of ancient taxidermy.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

Turkish adventurer antiques in the heart of the Grand Bazaar.

Breathtaking and huge 430 year old maps of Italy.

The second-largest gold nugget in existence, displayed in a Las Vegas casino conveniently named the Golden Nugget.

Daily jousts and dancing barrel makers in Munich's mechanical clock.

Modern technology and live displays tell the story of the Pacific during WWII for the Internet generation.

This memorial commemorating fallen Swiss Guards of the French Revolution has been called the saddest stone in the world.

Curious crustaceans support an obelisk from ancient Egypt that now stands in modern-day Central Park.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

Relics of the 1894 Midwinter Exposition continue to delight visitors today.

Golden Gate Park's historic collection of plants.

The restored and active Victorian-era final resting place of San Francisco.

Carnivorous plants, medieval aphrodisiacs, and the largest original wood structure glass conservatory in the western hemisphere.