Cave shrine on Monte Pellegrino.

Haunting graffiti left by prisoners of the Spanish Inquisition.

One of the most enjoyable bits of history at Coney Island and “the most romantic ride in the world.”

Visit the site of a subway powered by nothing more than air--and lots of it.

Beneath an ancient wishing tree lies an underground chapel with 12th-century frescoes and catacombs dedicated to a lady saint.

Wander through the Corridor of Wonders in these stunning limestone caverns.

The former atelier of Mario Cassisa is a treasure trove of paintings, sculptures, and artist books.

Built on a medieval synagogue, this church has a burial crypt, tunnel system, and Jewish ritual bath hiding deep underneath.

A series of caves, tunnels, and wells filled with fascinating figures and symbols.

A musical instrument played by the sea.

The medieval ferry service has been going strong since the 14th century.

An eccentric home in Sicily turns heads on a regular basis.

One fisherman has used his love of pebbles and shore to create a crazy garden of rocky art.

These morbid carvings remind churchgoers of the inevitability of death.

The remains of Crystal Palace Great Exhibition of 1851.

A relic of Victorian grandeur hides beneath a busy South London road.

This peeling mural of Adam and Eve was inspired by the greenhouses at Kew Gardens.

A Victorian park cemetery, standing on the site of what was once the Great North Wood.

This wildly-tiled artist's palace is a living and growing account of the creator's life, loves, and labors.

A charming 17th-century alley is lined with secondhand bookstores and antiquarian shops.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

A library built during San Francisco's pioneer times is a student's retreat, bibliophile's sanctuary, and chess player's delight.

Reverend Franzo Wayne King administers spiritual enlightenment through the music of the jazz legend.