Costa Rica's best known combat zone, used during the Battle of Santa Rosa.

This neon blue river gets its color from a unique mix of bacteria and volcano minerals.

The same water that fills a luxury resort’s pools feeds these free hot springs in the rainforest.

This Costa Rican topiary park is a surreal garden of unearthly delights.

This abandoned hospital is one of the most haunted places in Costa Rica.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

A 300-year-old tea shop that brought tea to the English people, not to mention the Queen herself.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

The final resting place of the "father of special effects."

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

The water-powered carriages are long gone, but for over a century this funicular railway has been the fastest route to the highest point in Paris.

19th century pendulum and a clock restored by a rogue group of guerilla artists.

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

Paris' linguistic guide to the international language of, yes, love.

The oldest stone house in Paris was built by its most famous alchemist.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

France's most famous cemetery, with some of its most curious tombs.

The vast, legendary catacombs hold secrets much stranger than stacked bones.