Lone Pine Gap
Lone Pine Gap is a gap through Red Mountain between Birmingham's South Highlands and Homewood. It was deepened by a cut for the Birmingham Mineral Railroad, exposing a section of the mountain's ore-bearing geology that was reported widely at the turn of the 19th century. The iron ore-bearing strata exposed included the 17-foot-thick "Big seam" and the 6-foot-thick "Irondale seam", both part of the Clinton formation.
Except for the Mineral Railroad, the gap carried little more than a "pig trail" Over the Mountain to Shades Valley, crossing the railroad bed on a "wagon bridge". The pass was made briefly more accessible by the Red Mountain Railroad Line, backed by the Clifton Land Company, which operated between 1889 and 1893. The roadway was gradually improved for adventurous motor-car drivers as 18th Street South., and later as part of the Montgomery Highway, until it was by-passed by the opening of the Red Mountain cut to the east.