Mauna Kea Access Road
22505.5 m · net rise 2080.0 m · total ascent 2095.2 m · overall 9.2% · evidence quality U (needs confirmation) · North Hilo · Hawaii · share
Shape: sustained — 33% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 1311 m.
Matches: Wikipedia — Mauna Kea Access Road — has its own article (Saddle Road to the summit observatories).
needs review short window divergence — treat short-window maxima here as provisional.
Gradient ladder what do windows mean?
| Window | Maximum | Located at | |
|---|---|---|---|
| 2 m (diagnostic) | ≈43% | 13268–13270 m | under overhead cover terrain reads 65.8% at 10613–10615 m across a structure — excluded |
| 3 m (diagnostic) | ≈38% | 13267–13270 m | under overhead cover terrain reads 51.4% at 10612–10615 m across a structure — excluded |
| 5 m | ≈31% | 14231–14236 m | under overhead cover terrain reads 33.5% at 10612–10617 m across a structure — excluded |
| 10 m | 22% | 14231–14241 m | |
| 20 m | 19.1% | 17142–17162 m | |
| 25 m | 18.7% | 17265–17290 m | |
| 50 m | 18.6% | 17265–17315 m | |
| 100 m | 17.3% | 17227–17327 m |
Measured on the mapped road line; moving the line 1 m either way reads 18.7–18.9% over 25 m.
Map
Check this route yourself: Google Maps route via their router · Street View at the base where coverage exists · geojson.io our exact measured line · OpenTopoMap
This climb's data: OCL JSON — the full gradient ladder, quality flags and provenance in the OpenClimb Ladder format.
Surface: mixed (33% unpaved), according to each state's road inventory: .
Access: Ranked 2026-09-08 (D27, inventory authority): the state road inventory carries 97% of the route as public road (private share 0%), which answers the OSM audit question (unnamed service way).
Measured, not vetted. This page records what the laser record shows about the road's shape — nothing more. Nobody has necessarily ridden or inspected this road for the survey, and a page here is not a recommendation and no guarantee that the road is open, surfaced, rideable or safe. Gates, private sections, missing rights of way and hazards do not show up in elevation data. Check access and conditions on the ground and make your own judgment.
Ridden it, or know better? Submit data for this climb no account needed · Share this climb
Route colour = gradient over a 25 m window: <10% 10–20% 20–25% ≥25%
© OpenStreetMap contributors · topo tiles © OpenTopoMap (CC-BY-SA) · vector tiles OpenFreeMap · aerial imagery USGS (public domain)
Profile
The map, profile and gradient chart share one position — move your pointer over them and the marker follows. Colors are the gradient bands; the shaded span is the steepest 25 m. Any 25 m figure is good to about a point either way (why).
Measurement card
| Elevation | USGS 3DEP (The National Map) — USGS 3DEP 1 m DEM, HI_Hawaii_Island_Lidar_NOAA_2017_B17 (collected 2017) |
|---|---|
| Resolution / CRS | 1.0 m grid, EPSG:26905; sampled every 1.0 m, bilinear interpolation |
| Tiles | x24y218, x24y219, x24y220 |
| Road centreline | OpenStreetMap (local PBF extract) |
| Quality status | evidence quality U; review flags: short window divergence |
| Analysis | OCL 0.1.0, analysis 0.1.0, run hi-run5-260908, calculated 2026-09-08 |
Provenance
{
"analysis_version": "0.1.0",
"sample_interval_m": 1.0,
"interpolation": "bilinear",
"smoothing": "none",
"gradient_windows_m": [
5.0,
10.0,
20.0,
25.0,
50.0,
100.0
],
"diagnostic_windows_m": [
2.0,
3.0
],
"elevation_crs": "EPSG:26905",
"elevation_resolution_m": 1.0,
"elevation_tiles": [
"data/cache/usa/hi-east/USGS_1M_5_x24y218_HI_Hawaii_Island_Lidar_NOAA_2017_B17.tif",
"data/cache/usa/hi-east/USGS_1M_5_x24y219_HI_Hawaii_Island_Lidar_NOAA_2017_B17.tif",
"data/cache/usa/hi-east/USGS_1M_5_x24y220_HI_Hawaii_Island_Lidar_NOAA_2017_B17.tif"
],
"calculated_at": "2026-09-08T04:14:27+00:00",
"road_source": "OpenStreetMap (local PBF extract)",
"road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
"osm_pbf_path": "data/cache/pbf/hawaii-2026-09-08-batch-band1.osm.pbf",
"osm_snapshot": "",
"run_id": "hi-run5-260908",
"elevation_provider": "USGS 3DEP (The National Map)",
"elevation_licence": "Public domain \u2014 USGS 3DEP 1 m DEM, courtesy of the U.S. Geological Survey",
"elevation_dataset": "USGS 3DEP 1 m DEM, HI_Hawaii_Island_Lidar_NOAA_2017_B17 (collected 2017)",
"elevation_tile_ids": [
"x24y218",
"x24y219",
"x24y220"
],
"climb_origin": "discovered",
"canopy_check": "unavailable \u2014 no surface model (DSM or point cloud) registered for this coverage",
"license": "ODbL-1.0",
"license_url": "https://howsteep.org/licensing"
}