Palo Alto has only one major crosstown arterial, Page Mill Road / Oregon Expressway, which connects freeways US 101 and I-280. It extends from US 101 to Skyline Drive, California State Route 35. It is also designated as County Route G3.
“County Route G3, more commonly known as Page Mill Road and Oregon Expressway is a short 4.5 mile (7 km) northeast-southwest arterial route that spans the lower peninsula region of the San Francisco Bay Area from I-280 to US 101. G3 runs through Palo Alto, California, unincorporated Stanford University lands, and the northwest corner of Los Altos Hills, California and is part of the Santa Clara County Expressway System.
G3 begins in the west at its interchange with I-280 in Los Altos Hills just south of Stanford University. It proceeds northeast as a four lane expressway over the rolling hills of Stanford University until it reaches Foothill Expressway (G5) with which it shares an at-grade intersection. East of Foothill Expressway, G3 descends down into the more urban areas of the lower peninsula going through the industrialized area of the Stanford Research Park located in Palo Alto. The road along this section has a reduced speed limit and several turnoffs along its length until it reaches El Camino Real (SR 82).
After SR 82, Oregon Expressway branches from Page Mill Road, which becomes a short two-lane street, and G3 follows Oregon Expressway under Caltrain tracks and onward for the remainder of its northeastward journey. Oregon Expressway resumes expressway status with limited access confined mainly to large intersections. G3 reaches its eastern terminus at its junction with US 101.
Page Mill Road (no longer designated G3) continues southwest of I-280 for 6 miles (9.7 km), a twisting two-lane road that climbs to Skyline Boulevard (SR 35) at the crest of the Santa Cruz Mountains. It passes the entrance to Palo Alto’s Foothills Park (which is accessible to Palo Alto residents and their guests only) and the Monte Bello and Los Trancos Open Space Preserves. Under the name West Alpine Road, the road descends west of Skyline Boulevard to a turn-off that leads to Portola Redwoods State Park, where the original Page (saw)mill is located. No artifacts remain at the mill site, which is accessible only by trail, either from Portola Redwoods state park or from Skyline Boulevard (SR 35)." (http://en.wikipedia.org/...)