Four Mile 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 Four Mile Road climb?

2.8 miles (4.5 km) at 10.7% on average, climbing 1,558 ft (475 m) from 1,207 ft to 2,766 ft. The steepest half kilometre averages 20.1%. That makes it a Category 2 climb.

Where does the climb start and finish?

It starts at 39.55596, -123.41775, where Four Mile Road leaves Covelo Road, and tops out on the road at 39.54422, -123.39057.

Is Four Mile 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.

• Mendo DriveCat 2 · 1.8 mi at 11.6% · 1,129 ft · starts 1.3 mi away
• Shimmins Ridge RoadCat 2 · 1.9 mi at 12% · 1,175 ft · starts 3.0 mi away
• Cherry Creek Road from Irvine Lodge RoadCat 3 · 1.5 mi at 8.3% · 676 ft · starts 3.1 mi away
• Third Gate RoadCat 3 · 1.5 mi at 7.5% · 584 ft · starts 4.4 mi away
• Skyview RoadCat 3 · 2.5 mi at 4.1% · 554 ft · starts 4.5 mi away
• Upper RoadCat 3 · 0.9 mi at 16.7% · 768 ft · starts 6.3 mi away
• Ridge Ranch RoadCat 3 · 1.5 mi at 8.6% · 666 ft · starts 6.5 mi away
• Bear DriveCat 3 · 1.3 mi at 11.2% · 741 ft · starts 7.2 mi away