This is a walk I led recently, and I like it so much I’m writing it down. As we visit these two major former quarries in the Piedmont bedrock block, we explore some distinctive terrain created during the Pleistocene epoch. We also experience how this beautiful landscape appealed to the people who developed this part of Oakland and Piedmont.

Three great geologic forces formed and shaped this landscape: tectonics, erosion and ice-age cycles. The hills of Piedmont arose roughly a million years ago in an incident along the Hayward fault that forced upward a block of Franciscan bedrock, along with its thick blanket of sand and gravel. The same rock and gravel are mostly buried under the rest of the East Bay, while the Piedmont block is about a kilometer higher.

After that initial uplift, erosion began stripping the bedrock bare and carving stream valleys into the gravel. It helped that the new-formed hills collected an extra share of rainfall from the Bay winds. This made a difference when an ice age came along and dropped sea level by several hundred feet. Each time — in about a dozen ice-age cycles over the last million years — the streams running off the Piedmont hills into the dry Bay basin combined to dig a valley that persists today as Lake Merritt.

The bare rock in the Piedmont block attracted quarriers when Americans first settled here, and later the valleys attracted the developers of fine residential tracts. This walk visits the valleys of three streams in the Piedmont block: Wildwood Creek, Bushy Dell Creek and Pleasant Valley Creek.

The geologic map shows the bedrock in blue and the gravel in gold; the lightest yellow is young sediment in today’s stream beds. The dark line is the route of this walk.

^{Qpaf, ancient gravel; Kfn, Cretaceous sandstone. From USGS MF-2342}

The digital elevation model, by stripping off the buildings and trees, helps visualize the shapes of the ground. The rock and the gravel create visibly different landscapes along the walk.

^{Base image from the National Map Viewer}

The street map is best for wayfinding. For your convenience, clicking these images opens them full size in a new window. Most of the route is within the city of Piedmont.

^{Route map created on gmap-pedometer.com}

The starting point is in the valley of Pleasant Valley Creek, better known as the Grand Lake commercial strip, at the Piedmont city line. This spot actually is where Bushy Dell Creek joins Pleasant Valley Creek, and we visit both watersheds later. But first we go up over the valley’s edge and into the watershed of Wildwood Creek. This bowl of low hills offers a sense of seclusion from the central city.

The route bends across the bowl toward the fringe of tall trees that marks the old Davie Quarry and the bedrock ridge on either side of it. Wildwood Creek runs beneath the streets in a culvert, but we pass two small bits of its headwaters later.

A rail line used to run up this valley along the creek, on today’s Lakeshore Boulevard. It began as a freight line serving the quarry, then became part of the Key Route passenger network after the quarry closed (and still later the 22 bus line). But our route stays off that line as we approach the tree-topped bluff where the bedrock begins and the Davie quarry lurks.

I wrote a separate post about the quarry itself that I won’t repeat here. This part of the walk offers opportunities to examine the stone that once helped pave Oakland streets and make quarry owners rich.

We then head to the north edge of the watershed. Along the way we pass exposures of the bedrock and glimpse two different bits of relatively untouched streams.

Climbing to the divide between the valleys of Wildwood and Bushy Dell Creeks, we cross Wildwood Avenue and pause overlooking Ritter Field. Bushy Dell Creek exits the hills of Piedmont Park, formerly a mineral spring resort, and enters a culvert here. The site never had a quarry; instead it was once part of Frank Havens‘s great estate, a public garden that, like other nice bits of the little city, was turned into playing fields for Piedmont citizens (see some old photos at historyofpiedmont.com).

We descend Wildwood Avenue along the divide before plunging into and across the valley of Bushy Dell Creek. The stream itself is hidden beneath Palm Drive and its historic trees, planted to go with Havens’s big garden.

We reach the opposite divide at Oakland Avenue, where Walter Blair’s cable car line once ran, and cross into the headwaters of Pleasant Valley Creek, where Blair established a major rock quarry next to his dairy farm. Today the former quarry has been rehabilitated as Dracena Park. I’ve written about this quarry in other posts too; here’s where to start.

The last leg of the walk goes back over the divide to the valley of Bushy Dell Creek and down to Nova Drive, which joins Wildwood Avenue to return to the starting point. At the base of Nova Drive is a little park by the former home of Sidney Dearing, a Black homeowner who was forced out of Piedmont by racists in 1924. It was an inevitable consequence of the whites-only restrictions that governed the entire nation at the time these lands were settled.

This walk is a pleasure at all times of year. Other posts featuring this area are here and here and here.

This entry was posted on 20 July 2026 at 7:47 am and is filed under Geoheritage, Oakland geology walks. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.