Jefferson Notch Road (south side)
5059.0 m · net rise 290.6 m · total ascent 313.3 m · overall 5.7% · confidence: good · New Hampshire · share
Shape: sustained — 32% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 108 m.
Not yet matched against documented climbs — the measurement stands on its own.
Gradient ladder what do windows mean?
| Window | Maximum | Located at | |
|---|---|---|---|
| 2 m (diagnostic) | ≈44% | 1066–1068 m | under overhead cover terrain reads 89.9% at 4204–4206 m across a structure — excluded |
| 3 m (diagnostic) | ≈39% | 1065–1068 m | under overhead cover terrain reads 73.5% at 4203–4206 m across a structure — excluded |
| 5 m | ≈29% | 1065–1070 m | under overhead cover terrain reads 53.8% at 636–641 m across a structure — excluded |
| 10 m | ≈25% | 4716–4726 m | under overhead cover terrain reads 29.7% at 635–645 m across a structure — excluded |
| 20 m | 19.3% | 4709–4729 m | |
| 25 m | 17.4% | 4704–4729 m | |
| 50 m | 12.6% | 3081–3131 m | |
| 100 m | 12.4% | 3039–3139 m |
Map
Check this route yourself: Google Maps route via their router · Street View at the base where coverage exists · OSM way 903936049 highlights the mapped road · 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.
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
© OpenStreetMap contributors · topo tiles © OpenTopoMap (CC-BY-SA) · vector tiles OpenFreeMap
Profile
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:26919",
"elevation_resolution_m": 1.0,
"elevation_tiles": [
"data/cache/usa/nh/USGS_one_meter_x30y491_NH_CT_RiverNorthL6_2015.tif",
"data/cache/usa/nh/USGS_one_meter_x31y491_NH_CT_RiverNorthL6_2015.tif",
"data/cache/usa/nh/USGS_one_meter_x31y492_NH_CT_RiverNorthL6_2015.tif"
],
"calculated_at": "2026-08-22T14:52:46+00:00",
"road_source": "OpenStreetMap (local PBF extract)",
"road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
"osm_ids": [
903936049,
903936050,
1532744870,
1532744871,
18846225
],
"osm_versions": {
"903936049": 3,
"903936050": 2,
"1532744870": 1,
"1532744871": 1,
"18846225": 21
},
"osm_timestamps": {
"903936049": "2022-11-26 18:26:43+00:00",
"903936050": "2022-11-26 18:26:43+00:00",
"1532744870": "2026-06-26 14:25:55+00:00",
"1532744871": "2026-06-26 14:25:55+00:00",
"18846225": "2026-06-26 14:25:55+00:00"
},
"osm_retrieved_at": "2026-08-22T14:52:46+00:00",
"osm_pbf_path": "data/cache/pbf/new-hampshire-260822.osm.pbf",
"osm_snapshot": "2026-08-21T20:21:11Z",
"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, NH_CT_RiverNorthL6_2015 (collected 2015)",
"elevation_tile_ids": [
"x30y491",
"x31y491",
"x31y492"
],
"route_summit_trim_m": 3229.0,
"route_summit_trim_loss_m": 295.5,
"climb_origin": "named",
"notes": "Gravel (surface chip per amended ranking policy). Highest NH public through-road pass; Base Road junction to the notch. Served by NH_CT_RiverNorthL6_2015. direction: as-is (2026-08-22): the way list is adjacency-ordered base->notch, but the chain's two ENDS are nearly level (junction 626.8 m vs far tail 621.8 m - the notch is interior) so ascent auto-orientation flips it; summit_trim cuts the northern tail past the notch. GNIS Jefferson Notch (-71.35369, 44.29674).",
"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.html"
}