Newly revised to take up part of the former 33 line, the 88 runs from the bedrock hills and uplands of Piedmont, through downtown Oakland, to downtown Berkeley. That’s three downtowns if you count Piedmont. It offers plenty of geologizing opportunities.

I will describe the journeys on this line in two directions from a central point well served by public transit, in this case the 19th Street BART station in downtown Oakland. (The 12th Street station works just as well.) It’s marked on this route map by the large dot.

^{Route map via gmap-pedometer.com}

Here’s the route superimposed on the geologic map. Both images open in a new window for your convenience.

^{Qms, Merritt Sand; Qhaf/Qhl, modern alluvium; Qpaf, Pleistocene alluvium; KJfs/KJfm/Kfn, Franciscan sandstone and melange.}

The northern leg of the 88 begins on the late Pleistocene dunefield (the Merritt Sand) that underlies central and West Oakland, crossing the great trench that holds I-980. As the bus heads north on Market Street, notice how the ground begins to slope down as it nears the edge of the dunefield.

At 21st Street the route enters the wide alluvial flat that stretches from here all the way through Richmond, described as “an immense plain” by the first Spanish explorers. Glimpses of the high Oakland Hills are the main geological sight on this stretch, so enjoy the deep-local neighborhoods along Market Street (in Oakland) and Sacramento Street (in Berkeley) instead as they go by (I like taking strolls here).

^{“Painted ladies” at 18th and Filbert Streets}

When the route turns right and climbs University Avenue, the steady hillward slope of this plain becomes clear. The route ends at Shattuck and Center Streets, gateway to the attractions of downtown Berkeley and some geological side trips.

Possible side trips from bus stops:
Lake Merritt channel (Broadway/12th St)
Pardee Home Museum (12th St/ML King Way)
Earthquake Memorial in the West Oakland platform (Market/16th Sts)
Lower Temescal Creek and Emeryville (Market/53rd Sts)
San Pablo Park (Sacramento/Oregon Sts)
Ohlone Greenway (University Ave/Sacramento St)
UC Berkeley campus (Shattuck/Center Sts)
Art concrete at UCB (Shattuck/Center Sts)
Remillard Park (Shattuck/Center Sts)
Avalon Hill (Shattuck/Center Sts)

The eastern leg takes you to the well-appointed sidewalks of Piedmont, saving you a tedious climb, but there’s scenery on the way. The boarding spot at Broadway and 20th Street is where the downtown dunefield gives way to another sedimentary platform, this one much older and consisting of alluvial sand and gravel with a topping of clay.

As the bus descends Grand Avenue, look ahead and see the ground rise to the same level in Lakeside Park on the other side of Lake Merritt’s north arm. We, however, turn left on Harrison Street for a few blocks of landfill on former wetlands at the mouth of Glen Echo Creek. This land is threatened by sea-level rise a few decades from now.

^{Ice-age platform of Lakeside Park}

At 27th Street the route begins to climb up a small stream valley into the ancient gravel hills of the Fan, up and over into the valley of Pleasant Valley Creek at upper Grand Avenue. Shortly after the bus begins a grinding climb up Oakland Avenue, it reaches bedrock at Latham Street and stays on it the rest of the way into the town center of Piedmont.

This little city, fully enclosed within Oakland, originated as a rugged outlying district of rock quarries that laid the foundation for the larger city around it.

^{Dracena Park, in the former Blair Quarry}

Possible side trips from bus stops:
Lakeside Park (Harrison St/Grand Ave)
Adams Point neighborhood (Oakland Ave/Perkinsway Path)
Morcom Rose Garden (Oakland/Olive Aves)
The Dracena Park quarry (Oakland/El Cerrito Aves)
The former quarry of Davie Tennis Stadium (Highland/Vista Aves)
The canyon and creek of Piedmont Park (Highland/Vista Aves)

^{Bushy Dell Creek in Piedmont Park}

This entry was posted on 27 October 2025 at 7:58 am and is filed under 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.