The European history of Mammoth Lakes started in 1877, when four prospectors staked a claim on Mineral Hill, south of the current town, along Old Mammoth Road. In 1878, the Mammoth Mining Company was organized to mine Mineral Hill, which caused a gold rush. By the end of 1878, 1500 people settled in the mining camp called Mammoth City. By 1880, the company had shut down, and by 1888, the population declined to less than 10 people. By the early 1900s, the town of Mammoth was informally established near Mammoth Creek. The economics of the original town was based on logging and tourism. The first post office at Mammoth Lakes opened in 1923.