Big Tenaja Peak

Hiked: 6/26/2026
Distance: 3.6 miles round trip on road and cross country
Summit Elevation: 2905'
Prominence: 776'
Elevation Gain: 920'
Elevation Gain (in Empire State Buildings): 0.7
Round trip time: 3 hours 30 minutes
Recommended water: 32 oz.
Parking/Fees: Adventure Pass at Tenaja trailhead
Difficulty: Moderate (heavy bushwhack, route finding, scramble)

Eric Su contacted me the day before to see if I was interested in climbing Big Tenaja (Peak 2905) on the east side of the Santa Ana Mountains. We agreed to meet at the Tenaja trailhead. Big Tenaja had no documented ascents in Peakbagger or Lists of John. Eric wanted to start in the dark to catch the sunrise over the marine layer. The pre-dawn coolness also reduced our chances of running into rattlesnakes. We both attributed the lack of ascents to the moat of dense brush and large boulders. We used Eric's proposed route going directly up the southwest slope. I put on my ratty hiking clothes saved just for such occasions and left the OC at 3:00 AM in order to meet at our 4:30 AM start. The marine layer was thick on Tenaja Road, slowing the final drive to 10mph. Darkness and fog combined to reduce my line of sight to about 15'. We walked about half a mile down Tenaja Road before ducking through a fence and starting the bushwhack. The brush was light at first with some open areas, then heavy brush and trees towered overhead. Eric led the way, navigating by GPS in the general direction of the summit. I followed with lightweight Fisker loppers, cutting branches to ease the ascent and leaving markers for the return trip. Half way up, we started hitting large granite boulders. Most were class 2-3, some class 4. I routed around class 4 with one exception: a large boulder/tree move where Eric pulled me up. As dawn seeped into the forest, we put headlamps away. With a couple hundred vert to go, I slowed down, but we were through the worst of the brush. There was a chance the summit boulder was going to be class 5, but we found it was a bulky, 20' class 2 slab. Still, I had to make use of a small manzanita tree to get onto the slab. On top, we were on one of several islands above the clouds. After photos, we started down, trying to follow our ascent path. Eric had an uncanny knack for route finding, while I needed to rely on the GPS since it all looked different to me. We got down safely with a few scratches for souvenirs and without seeing another person. It was a wild adventure, and one I would never have attempted on my own.