Mount Umunhum is the most prominent peak in the Santa Cruz mountain range, notable for the large cube structure on its peak. During the second world war the peak was an army base and the cube is the base of a radar dish installation that scanned the Pacific coast. Last September the newly constructed trial and rehabilitated peak was opened to the public, and I’ve been looking forward to visiting ever since.
The road actually goes right up to just shy of the peak, and there’s another trailhead 3½ miles from the top, from which the new Mount Umunhum Trail begins, at Bald Mountain, but I wanted a more challenging hike so I started at Hicks Road from Woods Trailhead. From here the peak is a little over 8 miles away with a little over 3,000 feet of climbing.
Mount Umunhum Road is closed from half and hour after sunset until sunrise (actually, as I would discover, 7am). At the entrance there’s an automated gate, and the Woods Trailhead is just on the other side, so you can’t park up earlier. I arrived 10 minutes before the gate opened and set off for the morning shortly after the gate automatically rose at exactly 7, setting off in the cool morning air, the sun already starting to beat down.
Woods Trail is a continuation of the dirt road the reaches across the Sierra Azul Open Space Preserve to Kennedy Trail and Lexington Reservoir, following the power lines. As it contours around the steep-sided valleys fantastic views across the open space and beyond to San José and the mountains on the far side are frequently visible. This section is actually reasonably flat, at first a descent to cross Guadalupe Creek, and then climbing back up to meet Barlow Road.
Barlow Road starts off steep and carries on that way for little while. This is definitely the steepest part of the hike. The trail first climbs up and over a ridgeline before dropping back down to again crossover Guadalupe Creek. At this time of year the creek is still flowing, not very fast, but enough to cool the air in the gully. The climbing resumes, and Barlow Road ends at the junction with the newly constructed trail to Mount Umunhum.
Up to this point I haven’t seen anyone else on the trail all morning, I can’t imagine many people hike down Barlow Road, although it does have some great views out and across the valley, but clearly the main attraction is Mount Umunhum itself. This changed quickly on the Umunhum Trail, popular with hikers, and deservedly so. Unlike the rest of the trail system in Sierra Azul, which is just old dirt roads that have been handed over to hikers, the trail to Mount Umunhum is the longest newly built trail in the Midpeninsula Regional Open Space system, graded for people rather than trucks.
The Umunhum Trail climbs gently, but persistently, through the rich and varied flora, the grasses still wet from morning dew. A mile up the trail a short detour leads to Guadalupe Overlook which has a great view out across the steep-sided valley and over to the valley below. Just up from the overlook the trail crosses over Guadalupe Creek a couple more times as it switchbacks up towards the summit.
On the final ascent the cube, visible since the very start, is starting to loom, standing on top of jagged rock outcropping. Shortly before the top the trail splits to loop around to the summit from the east or to join the road and approach from the west.
On the day of my hike however the east approach and the area immediately around the cube is closed. When the peak was reopened it involved a lot of cleanup of hazardous materials from the old army base, which was a big part of the cost and duration of the project. The cube, always white, was repainted to seal in the asbestos and lead paint covering it. However, when it rained in the winter the paint started to run, exposing the contaminants below, so its being worked on again to clean it up. In all my photos the cube has had the paint stripped revealing the raw concrete below, it’s much more prominent in its usual white.
Between the parking lot near the summit the top is 159 concrete steps, so perhaps I should take it back, this is the steepest section. At the top the summit itself has been restored to a rock garden and “ceremonial circle”, but the real treat are the views, which are fantastic. The 3 other peaks surrounding the bay area are all visible; Mount Tam, Mount Diablo, and Mount Hamilton, as well as the steep valleys and vast valley below.
Because of the car access the summit it thronging with people, so after spending a short period taking in the view I turn around and head back down. On the way down I see more people coming up Barlow Road and Woods Trail, although now later in the day it’s much hotter and less pleasant. In the late spring the early morning is definitely the best time to start this hike, I’m already back at home and resting before the more intense heat of late afternoon hits.