The California Gold Rush of the late 1850s expanded Napa City. After the first severe winter in the gold fields, miners sought refuge in the young city from snow, cold, floods and disease. A tent city was erected along Main Street. There was plenty of work in the valley for disillusioned miners. Many cattle ranches were maintained, and the lumber industry had greatly expanded. Sawmills in the valley were in operation cutting up timber that was hauled by team to Napa, and then shipped out on the river to Benicia and San Francisco.