Florida's railroads emerged in the 1830s amid Native American upheaval and territorial colonization. Many periods of development marked this fascinating heritage, but one era towers above the rest: the 1920s. It was then that Florida experienced a colossal land boom, one of the greatest migration and building stories in American history. People poured into the state as never before, real estate traded hands at breakneck speed, and the landscape added countless new homes, hotels, apartments, and commercial buildings. Florida's biggest railroads—the Atlantic Coast Line, Seaboard Air Line, and Florida East Coast—were unprepared for the tidal wave of traffic. Thus, the "Big Three" had to rapidly expand and increase capacity. Dozens of projects unfolded at great cost, by one estimate over $100 million. When the building frenzy ended, the railway map of the state stood at its greatest extent—some 5,700 miles. Further, the frequency of railway service within and to the Sunshine State reached an unprecedented level, never again to be repeated.