Siri Road Climb

We don't rate roads as safe or unsafe: crash counts can't say how risky a ride is, and roads people like to ride draw more riders, so they see more crashes. What the records show: no bike crashes were reported along the climb from 2021–2025.

How long and steep is the Siri Road climb?

0.6 miles (1.0 km) at 15.7% on average, climbing 525 ft (160 m) from 348 ft to 873 ft. The steepest half kilometre averages 16%. That makes it a Category 3 climb.

Where does the climb start and finish?

It starts at 38.4907, -123.0186, where Siri Road leaves Duncan Road, and tops out on the road at 38.48751, -123.0268.

Is Siri Road paved?

Yes, by its OpenStreetMap tags.

How is the category worked out?

From the climb's shape only: length in metres × average grade (%) of 16,000 or more for Cat 3, 32,000 for Cat 2, 64,000 for Cat 1 and 80,000 for HC. It describes how hard the climb is, not traffic or crashes.

Where does this data come from?

The climb is found from OpenStreetMap roads and USGS 3DEP elevation (every climb, not a list of famous ones). Access is from OpenStreetMap tags; gates and closures change, so obey posted signs. Crash counts are police reports in the California Crash Reporting System (CCRS) on data.ca.gov, counted where their map location is within 100 ft of the climb. The forecast is from the National Weather Service.

• Old Cazadero Road near HealdsburgCat 3 · 4.4 mi at 4.3% · 1,014 ft · starts 0.6 mi away
• Gabes Rock RoadCat 3 · 1.2 mi at 9.5% · 620 ft · starts 1.1 mi away
• Armstrong Woods RoadCat 2 · 5.5 mi at 4.6% · 1,332 ft · starts 1.2 mi away
• Chimney Rock Road near HealdsburgCat 3 · 1.2 mi at 12.5% · 778 ft · starts 1.4 mi away
• Magic Mountain RoadCat 2 · 1.6 mi at 13.1% · 1,076 ft · starts 2.0 mi away
• Chimney Rock Road from Austin Creek RoadCat 3 · 1.2 mi at 14.4% · 935 ft · starts 2.7 mi away
• Redwood Heights DriveCat 3 · 0.5 mi at 22.9% · 623 ft · starts 2.7 mi away
• Sweetwater Springs Road near HealdsburgCat 2 · 3.4 mi at 6.4% · 1,142 ft · starts 3.0 mi away