NO. 516 WELL, CSO 4 (PICO 4) - On this site stands CSO-4 (Pico No. 4), California's first commercially productive well. It was spudded in early 1876 under direction of Demetrious G. Scofield who later became the first president of Standard Oil Company of California, and was completed at a depth of 300 feet on September 26, 1876, for an initial flow of 30 barrels of oil a day. Later that year, after the well was deepened to 600 feet with what was perhaps the first steam rig employed in oil well drilling in California, it produced at a rate of 150 barrels a day - it is still producing after 77 years (1953). The success of this well prompted formation of the Pacific Coast Oil Company, a predecessor of Standard Oil Company of California, and led to the construction of the state's first refinery nearby. It was not only the discovery well of the Newhall Field, but was a powerful stimulus to the subsequent development of the California petroleum industry.
W. Pico Canyon Rd. 3.3W of 5. (This landmark is located on Pico Canyon Service Road. It is 1.4 west of the Mentryville park Parking lot.)
The road is paved, so we road our bikes, but we did have to walk them once the road got too steep for us. The ride home was fun but a little scary.
From the Mentryville parking lot, it is: 0.7 miles to Johnson Park/ 1.1 miles to the silver cylinder/ 1.4 miles to the landmark.