The ridge traversed by Manzanita Drive is one of Oakland’s highest residential areas, higher than 1400 feet. It’s the home-studded rise in the Oakland skyline to the right of Round Top in the blog’s banner image. Here’s the topographic view, from Google Maps:
. . . and here’s the matching part of the geologic map:
The ridge crest is held up by the Claremont Chert (Tcc), while Skyline Boulevard and Arrowhead Drive, running parallel just to its south, go through the crumbly Sobrante Formation (Tsm). (The other formations are the Orinda Formation, Tor, and the unnamed Eocene sandstone of upper Shepard Canyon, Tes.) Here’s the chert exposed at the west end of Manzanita; it and the next two photos click bigger.
The middle of Manzanita offers fine views of Round Top.
And the other end of Manzanita, past the unexpected Hills Swim & Tennis Club, is another saddle at the top of Shephard Canyon where the road to Canyon and Moraga crosses the hills.
More than anywhere else in Oakland, this is an island in the sky.