California Highway 25, also referred to as “Airline Highway”, cuts its way along the Diablo Mountain Range of Central California, offering motorcyclists a way to travel north-south through the state while avoiding the heavily trafficked US-101.
Airline Highway was originally named because before the advent of radio communications, airplane pilots had used the highway as a visual aid.
The most enjoyable portion of Highway 25 starts at the south where it intersects with Highway 198. From there, it’s a 51 mile stretch north to the town of Tres Pinos. Along the way, there are no services, no rest stops, only farms and cows.
Otherwise, Highway 25 actually goes further north, only about an additional 19 miles, where it intersects with US-101. Towards the south, it officially ends at CA-198, but continues another 40 miles to San Miguel, as Peach Tree Road and Indian Valley Road.
Three of the most enjoyable reasons to ride Highway 25 are the gorgeous views of hillsides and mountains along the Diablo Range, the golden grasses and oaks, and the near absence of traffic. We saw only a handful of cars coming the opposite direction the entire time, along with a few motorcycles.
Highway 25 offers some curves and twisties as you get closer to Tres Pinos in the north, but for the most part, it’s the southern section of grasses and hillsides, where the road runs more straight, that took our breath away.
Try to ride this highway in the Spring months, when the flowers are in bloom and the hillsides are green.
If you’re already planning to ride north or south along US-101, it’s really not much of an effort to take Highway 25 as a side route if you have the time. If you want to take the southern extension of Peach Tree Rd and Indian Valley Rd, keep in mind it’s a single lane only, though paved, with no service.