FLORIDA KEYS — In January 1912, the first Oversea Railway train rolled from the Florida mainland through the Florida Keys to Key West, forever changing the face of many of the previously isolated islands by connecting them with the mainland and each other.

A celebration to honor the historic railroad, lauded as the most unique railway in the world upon its completion, has begun in the Keys. Events are to culminate Jan. 22, 2012, the 100th anniversary of the inaugural train’s arrival.

Conceived by Standard Oil tycoon Henry Flagler, construction on the rail line began in 1905, motivated by an announcement that the Panama Canal would be built. Flagler thought Key West had the potential to be an important port and trade route with Cuba and Latin America, as well as a vital supply stop for ships entering or exiting the Panama Canal.

The railroad’s track stretched more than 100 miles out into open water, requiring trailblazing construction techniques and herculean efforts. At several points in the construction process, more than 4,000 men were working on the project. Flagler gambled nearly all of his wealth on the venture, which was so daunting and unproven that many outsiders called it “Flagler’s Folly.”

Officially named the Florida East Coast Railway’s Key West Extension, the line became known as the Oversea Railway and was sometimes referred to as “the eighth wonder of the world.” The bridges and viaducts connecting the Keys, including the landmark Seven Mile Bridge at Marathon, were regarded as an engineering marvel.

For more than two decades after the railroad’s 1912 completion, it carried passengers to the Keys and Key West, affording them a breathtaking sense of steaming across the open ocean.

The Oversea Railway’s heyday abruptly ended when a portion of the line was destroyed in a 1935 hurricane. Less than three years later, a narrow highway for automobiles replaced the tracks.

Today, many of the original railroad bridges still can be seen alongside the bridges that support the modern Overseas Highway, the contemporary connection from mainland Florida through the Keys.

Other reminders of the historic railroad include Pigeon Key, a five-acre island that lies beneath the Old Seven Mile Bridge at Marathon. A base camp for workers during construction of the original railroad bridge, the tiny island now features carefully restored structures and a museum dedicated to the railway and its builders.

Celebrations commemorating the Oversea Railway’s centennial year are being organized throughout the Keys. Planned elements include history tours showcasing Flagler sites, bicycling expeditions, educational presentations and explorations of Pigeon Key — all leading up to the 100th anniversary of the first train’s arrival in Key West.

Celebration highlights include “Flagler’s Speedway to Sunshine,” an exhibition and special event series that has already begun at the Key West Museum of Art & History at the Custom House in Old Town Key West.

The exhibition includes a re-created Florida East Coast railcar, a scale replica of a section of the Seven Mile Bridge, vintage footage of the journey from Pigeon Key to Key West, a film recounting Flagler’s story and the arrival of the first train, rare artifacts including a conductor’s uniform and railroad worker’s tool chest, and memorabilia that brings alive the fascinating story of the railroad that went to sea.

A comprehensive website focused on the Oversea Railway centennial, featuring a detailed schedule of events, is being established at www.FlaglerKeys100.com.

For more information about the Florida Keys & Key West, visit www.fla-keys.com. Information also can be found at www.facebook.com/floridakeysandkeywest, twitter.com/thefloridakeys and www.youtube.com/FloridaKeysTV.

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