Tombstone is a city in Cochise County, Arizona, United States, founded in 1879 by Ed Schieffelin in what was then Pima County, Arizona Territory. It was one of the last wide-open frontier boomtowns in the American Old West. From about 1877 to 1890, the town's mines produced USD $40 to $85 million in silver bullion, the largest productive silver district in Arizona. Its population grew from 100 to around 14,000 in less than 7 years. In 1881, it became the county seat of the new Cochise County.