Distance: 49 miles out and back
Elevation gain: 3200 ft (from RWGPS)
This is another of those “best in the area” rides—not a life-changing ride but one worth doing if you’re in the neighborhood. It’s in the midst of a network of southeast Bay Area roads that cyclists ride all the time and which I find sterile and barren: Mines, San Antonio Valley, Tassajara, Highland, Altamont Pass. All rolling grassy hills. But in the midst of this desert is Del Puerto Canyon Road.
On a map it looks like it would be featureless like all the others, but it’s through a little canyon of considerable charm. It winds niftily along a little creek (dry in summer), which means riparian plant life, canyon walls, lots of turns, and some shade. It’s also predominantly next-to-flat (the first 16 miles average 1-2%, and almost all the elevation gain is in the two miles before the summit), which the others aren’t, so it’s ideal for a day when you don’t want to work. Where RWGPS gets that elevation gain total, I don’t know. You can in fact control the effort precisely—the pitch goes from flat to imperceptible to moderate to steep, and you can just turn around when you’re worked as hard as you want to.
In addition, DPCR has one virtue that no other ride in Bestrides can claim: it’s 50 feet off Hwy 5, so from now on when you’re making that tedious drive from SoCal to NorCal or vice versa you can pull off midway and do a refreshing little out-and-back on the bike.
In Patterson, CA, on Hwy 5, take the Sperry Ave/Diablo Grande Pkwy exit, go west under Hwy 5 and take the immediate R turn onto Del Puerto Canyon Road. Park anywhere on the shoulder. Ride to the T at the end of the road, then ride back. You can begin at the other end, but the first 21 miles are uphill from the Patterson/Hwy 5 end so I ride it that way so the work is in the middle of the ride, not at the end. Straight off you see an eerie sight: a large, mature orchard where the trees are all dead. My guess is someone cut off their water.
After a couple of miles of moderate rollers through open grassy hill country, you enter the canyon and stay there until the summit at mile 21. A stretch of road has become graffiti central—as usual the messages range from “Love is…” to giant phalluses—but it’s short-lived. As with most desert riding, the beauty around you may not be immediately obvious, and I encourage you to take the time to get into your surroundings. Watch for hawks playing games with each other in the air above you.
After those initial rollers, the pitch increases gradually. For the first 14 miles, it’s imperceptible. Then it’s noticeable. At about 17 miles it’s substantial. The last 2 miles to the summit are downright hard (8-10%), made harder by the deterioration of the road surface. If you’re out for an easy day, turn around when it gets tough, knowing that you won’t be missing anything important. Someone has painted large mileage markers, large but so artfully incorporated into the centerline that they’re hard to see, to tell you exactly how far in you are.
If you continue on past the summit, the road descends the back side of the pass for 3 more miles, then dead-ends on Mines Road. Skip it if you don’t want to climb back up, though it isn’t steep.
I don’t enjoy the first three miles of the return from the summit, because steep descents over rough pavement suck. After that, it’s a nearly effortless ride back to your car. Every time I’ve done it I’ve had a easterly wind in my face, even when there was a strong northerly on Hwy 5, so I suspect that’s the norm.
The downfall of this ride may be the traffic. The first time I rode it I saw 2-3 cars total. The second time I met about 100 motorcycles head-on over a stretch of 10 miles. The third time I saw 4 cars. All rides were on weekdays. In addition, there are a very large municipal park, Frank Raines Regional Park, and a OHV playground about midway, both of which are closed in the off-season. I have no idea how busy the area is on a weekend when they’re open.
Even though it’s in a canyon, this ride is still dry and hot in summer, so I recommend doing it in spring, fall, or early morning. See Russell’s excellent comment below for info on traffic and water re-supply. After a very wet spring I did it in mid-April and the hills were already beginning to brown up.
Adding Miles: at the turn-around point you’re in the midst of a classic Bay Area ride, the “Mt. Hamilton Rd. out, Mines Rd. back” loop. To the R, Mines Rd. goes for miles, then ends near the southern-most point of our Morgan Territory Road ride. Mines Rd. was even on the Tour of California route one year—I remember standing on a climbing corner and watching a hard-working Lance Armstrong pass by me an arm’s length away. To the L, San Antonio Rd. climbs the back side of Mt. Hamilton and ends at the turn-around point of our Mt. Hamilton Road ride. I consider both rides tedious, and I don’t know anyone who has ridden up Mt. Hamilton from this side, which says something (but see Andrea’s comment below).
Afterthoughts: just across Hwy 5 from Del Puerto Canyon Rd. and unmissable is an Amazon “fulfillment center,” surely one of the largest one-story buildings on earth. Well worth a gawk.
A few miles into the ride, a large iron door is set into the rock wall. Thoughts of the mines of Moria are unavoidable. Can anyone tell me what it is? Perhaps it’s the eponymous “Puerto.”
Jay, the iron door in the rock you asked about is related to a short-lived narrow-gauge railway that operated in the canyon circa WWI and served some mining operations for minerals. The iron door does not block any entrance to a mine shaft, though, so the secret location of the Dwarves’ hoard is still safe…
There is NO potable water at Frank Raines Regional Park, which includes both the municipal park and OHV playground you mention. There is, however, potable water available to the public from a tap/faucet at Adobe Springs, although it is easily missed. Assuming a start near I-5, Adobe Springs is on the left side of the road, approximately 18.5 miles from the start of the ride as you have described it, (2.5 miles past the municipal park). Also easily missed is a white arrow painted on a large rock just before the turn. The tap is just out of sight within spitting distance of the main road. GPS coordinates: 37.408751, -121.409132
The OHV park is closed during fire season (generally mid-June to mid-October).
I live about an hour’s drive from this ride but make a point to ride it once every year in the early-to-mid-April timeframe—green hills, mild temps, and wildflowers!
I have ridden the backside of Mt Hamilton probably 20 times in my life. It’s my favorite climb. You haven’t climbed Mt. Hamilton until you do it from the Livermore side. But don’t do it in the summer—wait until the early spring or late fall. I have done it in July when it was 106. The last 6 miles are not for the faint of heart, and yes, it was part of the Amgen Tour several years ago when they started in Patterson and went up Del Puerto as a warmup, then continued on over Mines to the top of Hamilton.