[Nineties Flava]

Originally Posted by nei

Skimming a population density map, Westchester looks like it may have more very high density tracts (say, above 25 or 30k / sq mile) while Alameda has more with a lower thershold. It looks like there's few tracts above 15k/sq mile outside of Oakland and Berkeley.

Above 15K you're right for Alameda County sans Berkeley and Oakland, above 10K though Alameda County has considerably more than Westchester County.

Berkeley and Oakland alone though have a larger area >15K ppsm than Westchester County.

Originally Posted by City Data

Yonkers

Nodine Hill: 33,727 ppsm
Ludlow: 22,842 ppsm
Getty Square: 18,420 ppsm
Southwest yonkers: 22,071 ppsm


Mount Vernon: 15,578 ppsm

Peekskill

Downtown: 15,579 ppsm
Fort Hill: 15,422 ppsm
Artist District: 16,460 ppsm


White Plains

Battle Hill: 20,403 ppsm
Carhart: 19,298 ppsm
Fisher Hill: 15,405 ppsm
Fulton Street: 15,650 ppsm
Old Mamroneck Road: 18,349 ppsm

versus

Originally Posted by City Data

Oakland

Adams Point: 25,535 ppsm
Allendale: 19,578 ppsm
Arroyo Viejo: 16,169 ppsm
Bartlett: 25,344 ppsm
Bella Vista: 17,041 ppsm
Bushrod: 16,265 ppsm
Chinatown: 22,991 ppsm
Civic Center: 16,274 ppsm
Cleveland Heights: 15,966 ppsm
Clinton: 23,747 ppsm
Coliseum: 15,102 ppsm
Cox: 20,679 ppsm
Eastmont: 16,463 ppsm
Fairfax: 18,398 ppsm
Fairview Park: 16,914 ppsm
Fremont: 18,754 ppsm
Gold Coast: 17,281 ppsm
Grand Lake: 20,964 ppsm
Harrington: 22,480 ppsm
Harrison Street: 17,327 ppsm
Havenscourt: 15,268 ppsm
Hawthorne: 15,689 ppsm
Hegenberger: 18,482 ppsm
Highland Terrace: 17,582 ppsm
Iveywood: 18,980 ppsm
Ivy Hill: 29,238 ppsm
Jefferson: 17,343 ppsm
Lakeshore: 15,157 ppsm
Meadow Brook: 20,372 ppsm
Merritt: 24,413 ppsm
Oak Tree: 36,348 ppsm
Patten: 15,795 ppsm
Piedmont Ave: 16,315 ppsm
Rancho San Antonio: 19,151 ppsm
School Street: 15,497 ppsm
Seminary: 19,142 ppsm
St. Elizabeth: 20,802 ppsm
Tuxedo: 18,140 ppsm
Upper Peralta Creek: 19,870 ppsm
Waverly: 17,439 ppsm
Webster: 19,460 ppsm

Berkeley

College Avenue: 21,213 ppsm
Downtown: 16,747 ppsm
Gourmet Ghetto: 22,146 ppsm
North: 20,148 ppsm
South: 15,299 ppsm
South Berkeley: 16,242 ppsm
Southside: 23,029 ppsm
Telegraph Ave: 37,690 ppsm

The flatlands of Berkeley and Oakland are for all intents and purposes the extent of urban living in the East Bay, they're nearly a combined 60ish square miles though so that's not a small area. The Alameda County suburbs (Hayward, San Leandro, Albany, etc.) have much higher peak density than the Westchester burbs (Bronxville, Eastchester, etc). They don't compare well to NY small cities like Yonkers but that's somewhat of a false comparison anyway.