The grassy hills south of Antioch don't look industrial today. But in the late 1800s they were the Mount Diablo Coalfield, and people came from around the world to dig in it.
Coal country
In 1859, William C. Israel found coal while clearing out a spring on his land about six miles south of Antioch. More finds followed, and the coalfield went on to produce more than 4 million tons. Its low-grade coal was the only easily reached supply in California for a time, so it fueled railroads, ships and industry, and people called it 'black diamond.' Five towns grew up in the valleys. The biggest, Nortonville, peaked at about 1,000 people, according to Wikipedia. When better imported coal and oil took over, the mines closed and the towns emptied.
Rose Hill Cemetery
On a hillside between the Somersville and Nortonville townsites, Rose Hill Cemetery holds more than 200 residents of the coalfield. Some were miners killed on the job, but most were children who died of smallpox, scarlet fever, diphtheria and typhoid. Many graves were never marked, and the original records were lost in the 1906 San Francisco earthquake and fire. Ansel Adams photographed the cemetery's cypress trees in 1960.
The preserve
The East Bay Regional Park District began acquiring the land in the early 1970s, and the preserve opened in 1976. It now covers nearly 8,533 acres, according to the district. Visitors can walk into the first 200 feet of the old Prospect Tunnel, and the district offers guided tours of a former sand mine.
The Greathouse Visitor Center is open Fridays from 10 a.m. to 2 p.m. and on weekends from 10 a.m. to 4 p.m. Gates are open 8 a.m. to 6 p.m. through Oct. 31 and 8 a.m. to 5 p.m. in November and December. Parking is $5 when the kiosk is staffed. The main entrance is at the south end of Somersville Road in Antioch.