Black Diamond Mines Regional Preserve

My 8 and 9 year old completed the hike, it wasn't easy though. They did some rock climbing and enjoyed the views. There should be a sign stating clearly where to exit and enter the trails, we were right around a corner from the stairs that lead down and out but thought we were lost. We ran into our friends who showed us the way down. We started from the first long trail going up from the road/ parking lot so we were thrown off where it ended when we got to the other side/end. I had only been on this trail once before but started last time where we ended the hike this time. now I know where to go but for your first time, it can seem like you're off track of its not clearly marked

tl;dr: for those looking to hike the extensive trails here, be prepared to step in cow poop, deal with destroyed trails from the herds, and circumnavigate cows displaying aggressive behavior. Priority at this park appears to be cows > people.

Full review:

For years I have recommended Black Diamond Mines as my favorite of the EBRPD parks. Unfortunately leadership at this park has apparently decided to prioritize cows over people of late, and appears to be more "publicly subsidized ranch land" than public resource. (Before accusing me of hyperbole, a note that one of the few other hikers I encountered had been driven to carrying a fake cattle prod with him because of the number of times he's encountered aggressive cattle.)

For context, I usually do an 8.5-10 mile loop, so this does not refer to the mine tours or more developed areas. When I visited in late January after a week + without rain, I found that cows lined the trails for nearly the entirety of my 8+ mile hike, and that three times I needed to adjust my trail choice to accommodate either "ornery bulls" as they were described by a fellow hiker, or cows that were anxious of me being near their calves and didn't back down as I called to them/approached. Although the park is supposedly "dogs off-leash", I needed to keep mine on for the entirety of the hike because of the restrictrictions on dogs around livestock.

Not only was the presence of the cows themselves disruptive, but they had torn up the trails to the point that they were nearly impassible, and if I weren't already 4+ miles into my hike, I would have turned around to avoid them. Between trying not to roll my ankle in their hoof prints, and the futility of avoiding stepping in cow poop, it was a long way from being a restful communion with nature and appreciation of the park. (Attached pictures from different sections of trail, as well as a warning on what your shoes may look like after your visit.)

If the park system is so keen on prioritizing grazing in the parks, it would be great to either mark destroyed trails as "closed", or do what Walnut Creek Open Space has previously done and put electric fencing along the trails to keep the cows from destroying them while allowing people to still access the land. I'm not against the multi-use nature of the parks, but please don't call something a public park when in reality it's publicly accessible ranch land.