FWIW and off-topic, but (maybe) interesting: We have right here just ~50 miles East of Silicon Valley's hustle and bustle - a hiking/backpacking area that folks who do the High Sierras say is way more difficult than the High Sierras. I have hiked and backpacked in both places and tend to agree.
Henry Coe State Park is a vast back country area that is low altitude, so it can be way hotter than when High Sierra hiking/backpacking. Hiking there requires continuous elevation gains/losses in steep valleys which - when combined with the heat - is a killer situation. It's beautiful, serene, has bodies of water full of fish ... but boy is it tough to get in there. I wish I could have my RV air-dropped way back in there beside it's most remote lake!