The North London Mill is a gold mill in Park County, Colorado that commenced operations in 1883. In 1874, the first London mine was opened, named for the mountain it burrowed into. The London mines became some of the most productive mines of gold, silver and lead in the area. Between 1879 and 1889, some $82,000,000 of silver was processed through the North London Mill. Due to the rugged environment and high altitude, transportation of ore between the mines and mill was difficult and costly. Thus, the first rope cable-way in Colorado was built to carry ore down the 3300' drop from the mine to the mill.