North Peak, Mount Diablo, Eagle Peak & Mount Olympia

This route goes after Diablo's toughest, least-visited side first and saves the main summit for the middle of the day. I started before sunrise from the Morgan Territory Road trailhead, and the climb wastes no time — it's close to 2,900 feet of gain in under three miles straight up to North Peak, one of the steepest sustained trails anywhere in the park. The early light more than made up for the burn, though: the whole eastern approach lit up gold as the sun came up over the Central Valley, ridgeline after ridgeline glowing before the haze burned off.

North Peak itself is Diablo's rugged, road-less twin — nearly as tall as the main summit at 3,557 feet, but with none of the pavement, visitor center, or crowds. From North Peak I continued on to Mount Diablo's true summit at 3,849 feet, the one stop on the day with a paved road and a visitor center, before swinging out to pick up Eagle Peak's narrow, knife-edge ridge and then Mount Olympia, a shorter but relentlessly steep climb in its own right, before starting the long descent down toward Marsh Creek Road on the mountain's quieter eastern side.

Getting back was its own project. Rather than retracing the same brutal climbs, I walked out to Marsh Creek Road and then made the long road connection back to the Morgan Territory Road trailhead, turning what could have been a steep out-and-back into a real point-to-point loop. By the end the tracked GPS data had it at 24.2 miles and 7,890 feet of elevation gain over 9 hours and 27 minutes of moving time — comparable to the big multi-peak Diablo days, but on a route that barely overlaps with the standard Six or Seven Peaks loops out of Mitchell Canyon.

By mid-morning, a full cloud inversion had filled the valleys below, turning the whole eastern side of the mountain into a sea of fog with just the ridgelines poking through. Four solid summits, one enormous connector walk, and easily one of the least-crowded big days I've had anywhere on Diablo.