Black Diamond Mines is part of the Eastbay Regional Park District. Located just south of the Town of Antioch and it offers good hiking opportunityies with 65 miles of trails. Its close to work for me so I've started to head there after work to work on getting in shape for backpacking. The area dates back to the mid 1800 when several mines began operation to mine coal. Later in its history they began mining sand for use in glass making. The park is working to restore several of the mines for visitors to view in the future. Free maps can be obtained at the parking area. Much like other parks in the area this is a multi use park. Cows still graze the land here so watch out for the cow patties! They can also make the trails rough early in the season when the trails are wet. There are several backcountry camping spots with one located near the old Stewartville town site and a group site near the Star Mine. I believe that there is also a trail that connects this park with Mt Diablo. See the bulletin board or contact the park at 925-757-2620 for a schedule of programs about the natural & cultural history of the area. During times of extreme fire danger they will close the park.

I've found out that many of the ranch roads that are used for trails in the park can be extremely muddy in winter. One one recent hike I had to stop about every 30 steps to get the mud off of my boots. I quickly cut my route short. Three cloudy days later I went back and it was ok to hike, but barely. I think they graded the trails last fall which might be part of the problem but its given me a good way to judge when I can go hiking on certain trails.