We walked a couple of trails, explored the old coal mine, and checked out the cemetery...really…read morefascinating to see how far back those tunnels inside the caves go. The visitor center had a ton of great information and history.

Exploring the California State Parks list online a number of years ago, I liked the description and…read moremap of Black Diamond Mines Regional Preserve. It was neat in that there were historical building(s), a cemetery, and different parts of mines in addition to the natural landscape, plants, and animals to observe. I visited a few different times in 2018 plus or minus a year. One time I brought my friend Jinsol along and another time I brought family (my mom and dad). The park volunteers/workers were friendly when we encountered them. We appreciated the map(s) of the park, it helped with exploring. Some sites were more readily identifiable than others. My mom had difficulty on some of the steeper trails, though my dad faired well. Some parts of the mines had information displayed though were not open on my visits. One of my visits was during a heat wave, while the remainder were during relatively average weather conditions. Shade was sparse, though present, during the heat wave. Even in the shade however, the heat seemed to spread. On a different occasion I slipped and fell on a pathway that had a small section that was temporarily dominantly mud. A place requiring my full attention for traversing the trail system.

Perhaps unfairly, but as an outsider, I tend to view this part of Contra Costa County as, how do I…read moreput it diplomatically...snooty. There are tract homes that are really mansions in gated communities here. You get a pretty good indication when you take the Livorna Road exit off 680 and head toward the hills. There's a convenient parking lot at the staging area, and the walk begins along a tree-laden path that leads into the Shell Ridge Trail. This is where the open rolling hills provide some challenges to the calves. You eventually make it to the most picturesque portion of the hike on the Mokelumne Coast-to-Crest Trail. This is where the residential areas disappear and you're at one with nature...except for the occasional mountain biker. Small mouth was warranted during such disturbances, but they didn't prevent me from a scenic view of Mt. Diablo (photo: https://bit.ly/3hZ96M1). Now I could've gone deeper into Mt. Diablo State Park, but hey, I'm not a rugged mountaineer. Instead I made a turn and precariously made my way downward to the Alamo Trail. I didn't realize I exited the park until I saw distracted people on the path yelling into their mobile phones as they let their dogs do their business. Hey, where's your scooper, sister? I think with more thoughtful planning, you can probably avoid the ritzy people with their ritzy homes. Maybe not. RELATED - Exploring this part of Contra Costa County? Here's a collection of places I've visited and reviewed: https://bit.ly/2x1rlsD

This review is for the trail starting at the livorna road staging area…read more I really liked this trail. It's a lot of up and down. The map on all trails leaves out a few mountain top options, so I went off trail a few times and followed an alternative route. This is definitely a trail that you will need your map in order to stay on. I hiked on a cloudy September day, temperature around 75 to 80°. On a hot day with direct sunlight this would be potentially unbearable.

It would be nice if they updated their website since we are in the digital age…read more They charge everyone the same price and if your kids are smaller than a certain height, it's maybe a few dollars off. The larger water slides were closed, which was the main reason we wanted to come here but didn't get to experience. Had they mentioned on their website that the slides were not available, we would have planned a different day or brought younger kids instead of the big kids. The cabanas were not held down by anything and it was a windy day, I almost got hit by the cabana flying. Maybe have them closed and when someone does purchase it is when you would open them up for the guest. I don't know if people really reserved any cabanas but a few were being used but closer to closing time so I don't think they really reserved them and people just sat there since it isn't getting checked in my opinion. I don't miss like that bathrooms are available in the front and back of the park. The front bathrooms in the check in area have lockers and showers. There is also a bathing suit spin dryer. It seems for the lockers that if you bring your own pad lock you can store your things if needed. It's great they allow you to bring in food but not in coolers but bagged food take out is ok. There is also food available for purchase in the back. Treats and desserts in the front middle of the water park. Parking is shared with the community building not close to the entrance. So for my disabled friends like me, we had to walk even from a disabled parking spot. The park does provide tables and chairs. The cement picnic tables in front are near the treats vendor store. I don't recall what type of tables are in the back near the food but there were more there and by the kid's splash pad area. I would like to return when the large slides are open but I call next year and find out till then.

I want to give credit to all the lifeguards, they were paying good attention and nice to the kids:)…read moreGreat job . My son had a great time :) this place is nothing fancy but clean and fun for the kids to play and cool off. Get here early to get a good spot in the shade:)

Super park Perfect for a quick hike outdoors with kids !…read moreRock formations are unique and the scenery is pretty

Fun area to explore especially with kids. Wind caves and giant rocks to climb. There's a trail to…read morefollow called Travel Through Time. Easy but rocky. Not for flip flops. Clean public restrooms nearby.

Beautiful! Free parking!…read more Dog friendly! Just gorgeous! Amazing rock formations! Also, poison oak. Be aware. Open spaces like this make me happy. All of the reviews are spot on. Whatever kind of hike you want to do you will find it here. Note- once you start to enter Mt. Diablo there are no dogs allowed.

Free parking , clean bathroom and multiples trail connecting (you can even connect to Mt.Diablo…read morestate park ! Must visit and revisit

We've lived near here for years and this was somehow our first visit. Won't make that mistake…read moreagain. Walked in from Willow campground, settled in, and immediately felt that "why haven't we done this before" feeling. After dinner we hiked through Cottonwood campground and found a trail out the backside with a panoramic view that made the whole trip. The sunsets here are next level. Saturday's weather was perfect; we fished, caught and released a few nice ones, and just relaxed. The day-use and launch area was recently repaved and is in great shape. Now, the honest stuff: Friday was extremely windy (upside...zero mosquitos). The mosquitos showed up Saturday night, which is just nature doing its thing. The bigger nuisances were neighbor-related: a big group of kids with flashlights running around until 3am Night 1, and someone blasting bass while cruising the campground multiple times Night 2. Not the campground's fault, just worth knowing if you're a light sleeper or in a tent. Bathrooms: one was consistently clean, one was hit or miss. Toilet paper ran out and the exterior water spigot wasn't functional. Landscaping could use attention. Camp hosts were around but hands-off, no complaints, just not super visible. Bottom line: beautiful location, great fishing, gorgeous views and sunsets. The infrastructure needs a little TLC but nothing that would stop us from coming back. We'll be back for sure.

Only reason I don't give 5 stars is fishing from the bank is not the best. There is only one pier…read moreto fish off of and the water is full of vegetation that will snag you up. The camp hostess is great! The campground is very nice. I was surprised that you can have fires here. I will camp here again very soon

Over the Memorial day weekend, My wife and I and some friends decided to try something new on the…read morewater. Disco Bay Paddleboards was a great way to expand our recreational vocab and relax at the same time. The rates were fantastic and the owner Ron was very accommodating and helpful. We were even able to board with our dogs.. ( Great fun if yours isn't jittery!!) So much fun for the whole fam. I will Definitely return!

This is such a great place! Every family is appreciative of the services provided to their…read morechildren/youth. A huge shout out to the team!! They host FUN events for our neurodivergent kiddos/youth & their families all year round!! We'd be lost without you. Thank you for all you do for our communities!!

Be Exceptional has been such a great experience for my son he is autistic and some times can have…read morehis moments but the staff is well aware of how to handle challenges with him . The school also makes everyone feel special if my child is happy I'm happy !