Los Alamos Road Climb near St. Helena

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 Los Alamos Road near St. Helena climb?

1.3 miles (2.0 km) at 10.3% on average, climbing 686 ft (209 m) from 1,030 ft to 1,716 ft. The steepest half kilometre averages 12.5%. That makes it a Category 3 climb.

Where does the climb start and finish?

It starts at 38.48842, -122.57202, and ends at a gate at 38.48943, -122.59176.

Is Los Alamos 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.

• Cougar LaneCat 3 · 0.9 mi at 17.5% · 843 ft · starts 1.6 mi away
• Wildwood TrailCat 3 · 1.4 mi at 7.4% · 568 ft · starts 3.1 mi away
• Langtry RoadCat 3 · 2.1 mi at 5.4% · 597 ft · starts 3.3 mi away
• Mattei RoadCat 3 · 1.1 mi at 9.8% · 564 ft · starts 3.3 mi away
• White Oak DriveCat 3 · 1.7 mi at 6.4% · 587 ft · starts 3.8 mi away
• Adobe Canyon RoadCat 3 · 2.9 mi at 4.7% · 732 ft · starts 4.1 mi away
• Los Alamos Road from Melita RoadCat 2 · 4.0 mi at 6.5% · 1,381 ft · starts 4.1 mi away
• Saint Helena RoadCat 2 · 6.6 mi at 3.9% · 1,339 ft · starts 4.2 mi away