San Marcos Rd is a formidable climb (avg 8% over 3 miles) with gorgeous views of the area (there are both east- and west-facing sections) and relatively little traffic. Unlike its logical continuation, the Painted Cave Rd, San Marcos has excellent pavement thanks to post-landslide resurfacing and not many stints over 10%. I took CA-154 down for part of the way, but will never do that again: highway-speed traffic and sometimes no shoulder. San Antonio Creek Rd area, on the other hand, looked like a pleasant place to explore on bike.

This route includes all the major publicly accessible mountain-bound dead-end roads in West Goleta. The easternmost and westernmost ones (Fairview Rd and Farren Rd) involve climbing, but the rest of the route is relatively flat. Cathedral Oaks Rd, Glen Annie Rd, and Vereda Del Ciervo are particularly well suited for time-trial practice (few to no traffic lights, gradual elevation changes, little traffic or wide shoulder).