There’s a wedge of land between the southern end of Grizzly Peak Boulevard and Skyline Boulevard that belongs to the Sibley Preserve. (It’s the little knob on the left edge of this blog’s banner image.) It has good views all around, like this one looking north-northwest. Click the photo for a larger version.
The peak on the left is Grizzly Peak, 1754 feet high. The peak on the right is Vollmer Peak, 1905 feet high. Both consist of basalt. Grizzly Peak’s rock is basalt of the Moraga Formation, the same stuff exposed in upper Claremont Canyon and in Sibley itself. Vollmer Peak is held up by a slightly younger unit, the Bald Peak Basalt. The bulge between is Chaparral Peak; it and Grizzly are part of Frowning Ridge, which ends in the green ridge below Vollmer Peak in this photo.
Grizzly Peak appears to be unambiguously part of Oakland, nestled in a sliver of territory between the UC campus and the county line. It isn’t Oakland’s most northerly bit of land, though. Another bit lies north of Grizzly Peak Boulevard and Golf Course Drive. I’d like to visit both spots.