Twin Peaks Foothills Professional Review and Guide
"In the middle of the city is an outcropping of rock, predominantly composed of chert, basalt, shale, and sandstone. Subdividing the area was a daunting task, but short streets and an interconnecting network of stairways resolved the problem. While the short streets are in many ways comparable to those on the eastern side of the city, these hills are higher than either Telegraph Hill or Russian Hill. The Upper Market, Eureka Valley, or Castro (all names in use) neighborhood is also known for its gardens, cooperative neighbors, and attractive, renovated Victorians."