South Twin Oaks Valley Road Climb
- long (3.8 km)
- 2.3 mi
- long (3.8 km)
- of climbing (222 m)
- 728 ft
- of climbing (222 m)
- average grade
- 5.9%
- average grade
- steepest 500 m
- 10.1%
- steepest 500 m
Elevation profile
From 581 ft at the bottom to 1,309 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 South Twin Oaks Valley Road this week
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Is it safe to bike up South Twin Oaks Valley 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. The records here are also incomplete: most reports along it are filed under San Marcos, where only 8% of reported bike crashes have a map location, so the numbers here are too low. What the records show: 1 bike crash was reported on or beside South Twin Oaks Valley Road along the climb from 2021–2025.
Common questions about South Twin Oaks Valley Road
- How long and steep is the South Twin Oaks Valley Road climb?
- 2.3 miles (3.8 km) at 5.9% on average, climbing 728 ft (222 m) from 581 ft to 1,309 ft. The steepest half kilometre averages 10.1%. That makes it a Category 3 climb.
- Where does the climb start and finish?
- It starts at 33.13344, -117.16419, where South Twin Oaks Valley Road leaves Barham Drive, and tops out at San Elijo Road at 33.10701, -117.17334.
- Is South Twin Oaks Valley 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
- Crestwind DriveCat 3 · 0.9 mi at 10.7% · 531 ft · starts 2.3 mi away
- Attebury RoadCat 3 · 2.0 mi at 5.5% · 571 ft · starts 2.6 mi away
- San Elijo Road from Elfin Forest Road EastCat 3 · 1.7 mi at 7.4% · 653 ft · starts 3.1 mi away
- San Elijo Road near San MarcosCat 3 · 3.1 mi at 5.9% · 951 ft · starts 3.9 mi away
- Kaywood DriveCat 3 · 2.0 mi at 7.1% · 751 ft · starts 5.5 mi away
- Camino MayorCat 3 · 0.9 mi at 12.9% · 620 ft · starts 5.7 mi away
- La Honda DriveCat 3 · 1.4 mi at 8.6% · 623 ft · starts 6.3 mi away
- Lake Wohlford RoadCat 3 · 4.0 mi at 3.9% · 833 ft · starts 7.9 mi away
Places to ride to nearby
Bike crash hotspots nearby
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.