We're crossing from the Caribbean to the Pacific for today's Geo Quiz.

The Panama Canal is one of the world's busiest thoroughfares. Nearly 15,000 ships carrying 300 million tons of cargo passed thru it last year. But go back a few centuries when the canal or the railroad across the isthmus of Panama didn't yet exist.

Back then, the best way, and the shortest way, to get from the Caribbean side to Panama City was to travel on the Chagres River as far as you could. The rest of the way you had to go on foot or on a mule.

The well worn trail became famous over time and we want you to name it.

It was the route pirates used to flee to the Caribbean. Spanish conquistadors hauled off South American gold and other loot along this route to their awaiting treasure fleets. It was even traveled by gold prospectors heading for the California Gold Rush.

Isthmus of Panama

The trail is mostly neglected and overgrown by jungle now though parts of the historic trail remain.

Watch a video and hear first hand trail stories from some travelers along this historic trail (you'll never guess how they're traveling)