Underwood Mountain Road Climb
- long (9.9 km)
- 6.2 mi
- long (9.9 km)
- of climbing (316 m)
- 1,037 ft
- of climbing (316 m)
- average grade
- 3.2%
- average grade
- steepest 500 m
- 8.5%
- steepest 500 m
Elevation profile
From 3,553 ft at the bottom to 4,590 ft at the top. Grades are averaged over each half kilometre, from USGS elevation data, so short ramps can be steeper than they show.
Weather at the top of Underwood Mountain Road this week
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Is it safe to bike up Underwood Mountain Road?
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.
Common questions about Underwood Mountain Road
- How long and steep is the Underwood Mountain Road climb?
- 6.2 miles (9.9 km) at 3.2% on average, climbing 1,037 ft (316 m) from 3,553 ft to 4,590 ft. The steepest half kilometre averages 8.5%. That makes it a Category 3 climb.
- Where does the climb start and finish?
- It starts at 40.69021, -123.41467, and tops out on the road at 40.73889, -123.44153.
- Is Underwood Mountain 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.
Other climbs nearby
- Corral Bottom Road from Hyampom Mountain RoadCat 2 · 4.9 mi at 5.4% · 1,401 ft · starts 2.6 mi away
- Corral Bottom RoadCat 3 · 5.0 mi at 3.2% · 850 ft · starts 2.6 mi away
- Pattison Peak Jeep RoadHC · dirt · 5.6 mi at 11.7% · 3,445 ft · starts 4.9 mi away
- Lake Mountain Road from Lower South Fork RoadCat 3 · 1.7 mi at 9.2% · 850 ft · starts 5.1 mi away
- Underwood Mountain RoadCat 1 · 7.5 mi at 6.6% · 2,612 ft · starts 5.3 mi away
- Kerlin Creek RoadCat 1 · dirt · 5.7 mi at 7.7% · 2,336 ft · starts 5.8 mi away
- Pelletreau RoadHC · dirt · 11 mi at 6.6% · 3,789 ft · starts 6.0 mi away
- Fir Root Springs RoadCat 2 · 3.1 mi at 7.7% · 1,273 ft · starts 6.2 mi away
Found from OpenStreetMap roads and USGS 3DEP elevation; ranked on shape only. Category 3: 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. Crashes: bike crashes reported within 100 ft of the climb, 2021–2025, from the California Crash Reporting System (CCRS), counted only where the report has map coordinates. Weather: National Weather Service. Access from OpenStreetMap tags; obey posted signs. How the data works.