This morning I made a circumambulation of Piedmont without setting foot in it, while also incorporating pedestrian stairways and paths. There was something to see at every step; here are two highlights. The first is the charming hidden street of Glenwood Glade in the Fernwood district (what I would have called northern Montclair), where I snapped this verdant front yard with indigenous boulders. The whole street runs directly upon the Hayward fault. I would enjoy it now, because it isn’t likely to survive the next major rupture.
Then below is the Zion Lutheran Church on uppermost Park Boulevard, isolated on the very edge of Piedmont overlooking Dimond Canyon. Why would a church be dug into a bedrock hillside? The answer is, it wouldn’t; this is a former quarry. I stayed across the street, not wishing to touch Piedmont soil, but it looked like massive Franciscan sandstone, just as it’s mapped.
The roadway of Park Boulevard through Dimond Canyon is so massively reinforced that I suspect there was a railway there first. Does anyone know the history there?
Oakland Geology 
9 April 2008 at 3:19 pm
I don’t see any sign of a railroad on Park Blvd in old USGS maps, although Shepherd Canyon Road is shown as one. The Wikipedia article on Montclair says that Park Blvd was originally a logging road, so maybe that is why it was built so heavily.
9 April 2008 at 4:28 pm
I just looked at all the old maps online at lib.berkeley.edu/EART/ and as you say, they show only a regular road up the side of Dimond Canyon. But that sucker is built strong, in typical Depression-era concrete. As I understand it, logs were sent down Sausal Creek itself, back in the 1850s.
16 April 2008 at 4:41 pm
I have heard the logging railroad theory as well. And yes, there was a railroad that ran in Shepherd Canyon. It was called the Sacramento Northern and ran from San Francisco, to Oakland, Sacramento and then to Chico. See my website’s rail and wire section for details and maps of the route.
18 April 2008 at 3:48 pm
Thanks for the post, Daniel. Glad to see people passionate about other aspects of Oakland history. The old Sac Northern railbed is a pedestrian path north of Route 24, and in Montclair there’s a new pocket park called Short Line Park where the railbed meets Thornhill at Moraga/Mountain Boulevard.