I bike to & from Rockridge BART in Oakland -- 5 miles, mostly downhill, in the morning (usually chilly in the bay area!), then 12 miles, mostlly uphill (1200+ feet of climb) on the way home. Some busy streets, and a couple of congested intersections, but mostly low traffic residential routes.
Work in SF, commuting from Oakland. Will ride close to 8,000 miles this year. Like to do weekend rides on the SF peninsula, Santa Cruz mountains, or east bay hills (including Mt. Diablo).
My favorite is a CalTrans story.... Riding on "open" bike path through Lake Temescal on the way to work. Asked some fence guys to move their truck off the path. They responded with flexed muscles & rolled up sleeves to tell me the route was "closed." Ultimately got apology from CalTrans and president of company that was sub-contracted for fence.