The Shenhai Well is located in Changyantang on the North Street of Da'an District in Zigong City, Sichuan Province.

The Shenhai Well was constructed between 1823 and 1835 during the Qing Dynasty (1644-1911) and has a depth of 1,001.42 meters -- the world's first well of more than 1,000 meters deep. Each day the well spouted over 10,000 dan (1 dan = 50 kilograms) of black bittern and produced over 8,500 cubic meters of natural gas that could heat more than 80 caldrons of salt. Until 1940 the well continued to produce bittern and between 4,800 and 8,000 cubic meters of natural gas. After one and a half centuries of work, the well's underground facilities suffered some severe damages. Following some repairs, the well can still produce over 1,500 cubic meters of natural gas per day.

The Shenhai Well covers an area of about 1,500 square meters. Its main constructions include mills, huge workshops, kitchens and storerooms. A comprehensive renovation project was carried out in 1984 to restore the well's former style and features. At present at the Shenhai Well one can watch demonstrations of the traditional techniques used in well-drilling, natural gas transport and bittern extraction in ancient China.