Central City/Black Hawk Historic District and funds as a result. Central City/Black Hawk Historic District The Central City/Black Hawk Historic District is a National Historic Landmark District that encompasses Central City and Black Hawk, Colorado. They are adjacent former gold mining camps in the Front Range of the Rocky Mountains in Gilpin County, Colorado, United States. For a time, the area was known as the Richest Square Mile on Earth. The district was designated a National Historic Landmark on July 4, 1961. On May 5, 1859, John H. Gregory discovered a rich deposit of gold in hard rock, the first such discovery in the Rocky
History of the London Underground South London at Kennington, this opening in 1926. Although physically connected, the lines were still officially named the City Railway and Hampstead & Highgate line. The lines were to be known as the Edgware, Highgate and Morden and the Morden-Edgware until finally renamed the Northern line in 1937. Also during the 1920s the original tube gate stock was replaced with 1,460 cars of Standard Stock with air-operating sliding doors, except for the Central line where the cars were refurbished. Busy central London stations were modernised with escalators replacing lifts. Unlike other railway companies in the London area, the Met was