Black Mountain via Rhus Ridge is a 9.8 mile out and back trail located near Los Altos, California that features beautiful wild flowers. The trail is rated as difficult and primarily used for hiking, walking, and trail running.
Towering over Silicon Valley, waaaay back to the rear of Rancho San Antonio, lies 2812' Black Mountain. Starting at the little-known Rhus Ridge parking lot, you can enjoy a healthy workout and a grand panoramic view of Silicon Valley.
It was ok, not great. About 10 miles, with elevation mostly in the beginning and the end. Total of 2500 feet elevation gain. The views were nice, but the end of the trail was sort of sad. Ended up near a road. Was wet/muddy at places, but not too bad. Spotted some nice birds and rabbits, otherwise not much wildlife anywhere else.
Trail is near to North San Jose. There are 2-3 trails connecting to same peak, the one we did was via Rhus Ridge. Total distance: 9.8 miles, Time taken: 3.5 hours.
About the trail path: Starting mile is elevated by 30 to 35 degree up, following 2 miles is slightly flat, but further again there's uprise by 20-30 degree, overall that makes it a hard trail. Across the trail there's of-course lush green view of trees, and at the peak there is a tiny camp ground, 4-5 sites, didn't camp though.
This is a long, fun hike, though would not recommend it on warmer days. It was a pretty steep start and lasted for about a mile, till we hit the black mountain trail. The black mountain trail is mostly flat with a few ups and downs and is around 3.9 miles. The last section is pretty steep and mostly exposed. Lots of fence lizards on the trail and in parts some dried wildflowers. All in all a strenuous but fun hike!