Number 12, a coal-fired steam locomotive, transported travelers from Johnson City, Tennessee through 66 miles of Blue Ridge Mountains to Boone, North Carolina. It was part of the East Tennessee & Western North Carolina Railroad, which ended operations in the area in 1940. Because of its shrill sounding whistle that resounded through the mountains, excited children called, "Tweetsie is coming". Proud engineers and railroaders were not very fond of the name, but it stuck.

Listed on the National Register of Historic Places, Tweetsie has been restored to its former glory and once again carries passengers at its popular theme park. Tweetsie Railroad is located on US 321 between Boone and Blowing Rock.