Mount Diablo hovers above the East Bay landscape as the 4,000 foot high menace promising to dish out some sort of bizarre torture to all those who intend to scale it on two wheels. It is also the most frequented long climb by bike riders on the entire west coast. I have pedaled up the mountain in every season of the year and Diablo never fails to disappoint in what it has to offer. Last year during the stage of the Tour of California bike race that finished on its summit, millions of earwigs emerged out of trees in plague like swarms that descended on the spectators. Hours after the event, they were still annoyingly crawling out of my clothes. Yuk! However; the sight of the podium girls shrieking and swatting helplessly at the swarms of insects was purely comical.
During the summer months, rattlesnakes, tarantula’s, and blazing hot heat are frequent companions. The winter months can offer snow, cold temperatures and gale force winds. Other times, flowering shrubs that smell like decaying animals attract hoards of pesky flies. Timed just right, the experience of the ride can overcome all the perils that Diablo entails with its sweeping views of the San Francisco Bay, the inland Bay Area valleys, the snow capped Sierra Nevada to the east and Mt Hamilton to the south.
To begin the ride, I would suggest starting at the shopping center at the northeast corner of Camino Tassajara and Diablo Road in the town of Blackhawk. A rolling five mile start with decent shoulders up Blackhawk Road is a good warm up before you make the right hand turn into Mount Diablo State Park. My most recent ride was with my two Swiss-Italian riding pal’s, one of which, Stefano, was a leader in the Giro d’Italia in the late 80’s.
Officially, the start of the long climb begins at the faded white stripe in the road as you pass Athenian School. You can also make the trek up Diablo from the North Gate on the Walnut Creek side of the park, however getting there is not as easy and the road quality is much poorer until the two roads merge at the junction seven miles up the road. Back at the beginning at Athenian, you will have 11.3 miles of riding ascending 3,250 vertical feet along very smooth asphalt.
The first 3.5 miles climbs up the south face of the mountain in a series of switchbacks until you reach the pay station gate. This is where I lost one of my Italian pal’s to a busted spoke that turned completely “taco’ed” his rear wheel. It was nice to get a break from the constant running dialog of alternating German-Italian languages as the next couple of miles transitioned from the southern side of the mountain to the northwestern face with the visitor center at the top becoming faintly visible in the distance.
A long upward straightaway through the grassy BBQ Terrace lofts up through the 2,000 foot elevation marker and it as this point that you will notice cooling temperatures no matter what season you are in. Typically, there is a 20 degree variance between the bottom to top. Last week, it was 64 when I started at the bottom and a very chilly 44 at the summit with 25 mph winds tossed in to make it feel artic like to Lycra clad wheel spinners. The suggestion of dressing in layers should be taken seriously.
At the junction gate, where both the south and north road meet, begins the toughest portion of the ride with an unrelenting grade of between 7-10 percent for the last 4.5 miles. Fortunately, I had Stefano on the front, blocking the wind effortlessly shouting out encouragement “Strong” while shaking a fist or he would be commenting on the scenery “bellissimo” while I was humped over my handlebars trying to survive. Either way, it was nice to have him along for the ride. The final 300 yards to the visitor center pitch upwards to 17% until you see the sign that displays Mt Diablo summit 3,849 feet and the satisfaction of surviving one of California’s most iconic climbs. Thank you Stefano!
A nice treat inside the visitor center are the cold drinks and energy bars for sale which are a very welcome sight to the tired and dehydrated. After getting refreshed, it is 25 minutes of pure gliding downhill back to Athenian. I will caution that nearly all of the cycling accidents on Diablo are on the downhill descent as riders overcook corners or collide with cars passing going uphill. Slow down, the view going down should be experienced not raced.