Great campground, stayed 4 nights in December. Highlights include sunrise views over the lake and hills with rolling fog, wild turkeys everywhere, smell of eucalyptus, warm showers, and scores of dedicated staff who genuinely care about this place. Sites are also nicely-spaced apart. (Though this also has the drawback that many of them are a significant walk to either the entrance or to bathrooms).

Only bummer was that in winter a lot of the best sites are closed. Also, not that there's a ton they can do about this, but the eucalyptus trees shed a ton of bark and so the roads are littered with them giving the place a kind of constant "just-survived-a-storm" kind of feel (at least when it's windier).

Most no-hookup sites are flat. 47 was the one I settled in since it is closest to the showers / sink for washing dishes and also has a little bit of lake view.

Just know that it's a hilly and winding drive in. Figure ~30 minutes from Castro Valley, the nearest town.

ATT data signal was modest (5-25mbps). T-mobile was basically non-existent.

This campground opened in August 2021, so the facilities are still brand-spanking new. They haven't yet installed the washer/dryer and haven't yet locked in a vendor to operate the camp store, but I'm told those things are coming.

What they do have are scores of hookup sites for $60 / night and three tent / drive-in no hookup water-only sites for $45 / night. The sites are close together and things are relatively packed in, but it doesn't feel overwhelming since there's plenty of open space and people are pretty friendly here.

The best parts about this campground in my opinion are:

• close to town
• excellent cellular reception on all carriers
• warm / hot and clean showers + other facilities
• nice sound of train off in the distance at night
• sunrise views
• stunning walks in the coyote hills and bird-watching in the estuary to the north

Gate closes at 10PM, but you can exit the park over the tiger teeth at any time if you need to. Highly, highly recommend giving this park a stay if you're passing through the Bay. Even if it's a little pricier, you're so close to town you can take care of some errands and not have to drive all the way to the other campgrounds to settle in for the night.

Mt. Diablo SP has 3 campgrounds: Live Oak, Juniper, and several first come first serve sites at the junction of South Gate and North Gate roads about 2000ft up the mountain.

Live Oak is the closest to the entrance (and town), and features some cool rock formations to explore, but it's colder, has terrible cellular data service, and doesn't quite have the sunset / sunrise views that Juniper has.

Juniper is way up there, plan for a 45 minute drive from town to the top, longer if you are doing it on a weekend when you'll be waiting to pass cyclists (be very careful, do not pass on blind corners, this is a cycling destination). But it is absolutely worth it for the views of the east bay, and on a clear day, all the way to SF and the pacific. Truly one of the best camping views I've had.

Juniper had decent 10-15mbps ATT cellular service in most site locations, and also decent t-mobile, but ping was slow. The best sites at Juniper if you're sleeping in your vehicle are the flat ones down by the parking lot and vista (18, 20, 22). Note that most of the sites on the west side are not flat for a vehicle. Fine for a ground tent. Lot's of wind up this high, and not a lot of shelter, so plan accordingly. Water is off, probably forever as CA will be in perpetual drought, so plan for that as well.

Only reason for 4 stars is that they lock you in at sunset; if you want to leave you have to call the fire department to open the locked gate, it's not like a tiger-teeth exit but no entry kind of situation. This significantly reduces flexibility, but I can understand why they don't want a bunch of cars trying to race up and down the mountain after dark.

Of the 200+ sites in the south campground, none were occupied. It was dark, facilities were shut down for the season, host was off duty. Ghost town. One other car pulled in after I'd made camp, but I'd already decided to bail for the KOA in Leavenworth. Did not stay the night.

Tmobile 5G was good: 50-80mpbs, same with ATT.

Utility site #1 flanks the beach and is probably best in the place. #2, #3, #4 are IMO best after that as they move away from the beach and then curve around in ascending order.

Some neighbor noise, sites are close, but was not busy. Plenty of first come first serve spots available in off-season. Tent sites are up on the hill shrowded in trees, so more shelter but fewer views. Depends on what you're after.

• T-mobile 5G: solid, 3bars, 50-80mbps

• ATT LTE: similar.

Listen for owls, watch for fishermen crawlers in the AM.

Rolled in late at night on an audible after campground at Lake Wenatchee didn't work out. Great tent sites, with decent spacing between them. This place is big, but didn't feel too crowded - at least during off-season. Super clean facilities, warm bathrooms, good provisions at their on-site store. Beautiful river walk, good proximity to town.

T-mobile 5G: pulling down 80-100mbps consistently, video calls were a breeze. ATT LTE: similar.