{
 "ocl_version": "0.1.0",
 "name": "Arrow Lane",
 "slug": "arrow-lane",
 "confidence": "A",
 "reported_claims": [],
 "ladder": [
  {
   "window_m": 2.0,
   "max_gradient_pct": 31.99425848700912,
   "diagnostic": true,
   "flags": [],
   "start_distance_m": 584.0,
   "end_distance_m": 586.0,
   "start_elevation_m": 480.2361492839441,
   "end_elevation_m": 480.87603445368427,
   "min_gradient_pct": -18.10680933915023
  },
  {
   "window_m": 3.0,
   "max_gradient_pct": 30.05339655834594,
   "diagnostic": true,
   "flags": [],
   "start_distance_m": 583.0,
   "end_distance_m": 586.0,
   "start_elevation_m": 479.9744325569339,
   "end_elevation_m": 480.87603445368427,
   "min_gradient_pct": -14.123923414162695
  },
  {
   "window_m": 5.0,
   "max_gradient_pct": 28.107066110312644,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 581.0,
   "end_distance_m": 586.0,
   "start_elevation_m": 479.47068114816864,
   "end_elevation_m": 480.87603445368427,
   "min_gradient_pct": -12.783715251732701
  },
  {
   "window_m": 10.0,
   "max_gradient_pct": 24.733286274480406,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 577.0,
   "end_distance_m": 587.0,
   "start_elevation_m": 478.62404771143315,
   "end_elevation_m": 481.0973763388812,
   "min_gradient_pct": -11.842561249559367
  },
  {
   "window_m": 20.0,
   "max_gradient_pct": 23.132145753448867,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 567.0,
   "end_distance_m": 587.0,
   "start_elevation_m": 476.4709471881914,
   "end_elevation_m": 481.0973763388812,
   "min_gradient_pct": -10.91690640607652
  },
  {
   "window_m": 25.0,
   "max_gradient_pct": 22.66587993990106,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 562.0,
   "end_distance_m": 587.0,
   "start_elevation_m": 475.4309063539059,
   "end_elevation_m": 481.0973763388812,
   "min_gradient_pct": -10.71172284752106
  },
  {
   "window_m": 50.0,
   "max_gradient_pct": 20.384201760340375,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 537.0,
   "end_distance_m": 587.0,
   "start_elevation_m": 470.905275458711,
   "end_elevation_m": 481.0973763388812,
   "min_gradient_pct": -9.613819551490678
  },
  {
   "window_m": 100.0,
   "max_gradient_pct": 17.482820277098313,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 527.0,
   "end_distance_m": 627.0,
   "start_elevation_m": 469.2324559275103,
   "end_elevation_m": 486.7152762046086,
   "min_gradient_pct": -7.620349525036772
  }
 ],
 "shape": {
  "ascent_concentration": 0.527,
  "concentration_window_frac": 0.25,
  "longest_pitch_10pct_m": 78.0,
  "shape_class": "stepped"
 },
 "length_m": 1075.7734080234197,
 "start_elevation_m": 458.6206339257971,
 "end_elevation_m": 484.35822230078276,
 "endpoint_gain_m": 25.73758837498565,
 "overall_gradient_pct": 2.3924730043545877,
 "accumulated_ascent_m": 46.25636310122155,
 "window_maxima": {
  "max_5m": {
   "gradient_pct": 28.107066110312644,
   "start_distance_m": 581.0,
   "end_distance_m": 586.0,
   "midpoint_distance_m": 583.5,
   "start_elevation_m": 479.47068114816864,
   "end_elevation_m": 480.87603445368427,
   "start_xy": [
    659522.2519548109,
    4680234.183351795
   ],
   "end_xy": [
    659518.0708446302,
    4680231.441396716
   ]
  },
  "max_10m": {
   "gradient_pct": 24.733286274480406,
   "start_distance_m": 577.0,
   "end_distance_m": 587.0,
   "midpoint_distance_m": 582.0,
   "start_elevation_m": 478.62404771143315,
   "end_elevation_m": 481.0973763388812,
   "start_xy": [
    659525.5968429556,
    4680236.376915858
   ],
   "end_xy": [
    659517.2346225941,
    4680230.8930057
   ]
  },
  "max_20m": {
   "gradient_pct": 23.132145753448867,
   "start_distance_m": 567.0,
   "end_distance_m": 587.0,
   "midpoint_distance_m": 577.0,
   "start_elevation_m": 476.4709471881914,
   "end_elevation_m": 481.0973763388812,
   "start_xy": [
    659533.9590633172,
    4680241.860826016
   ],
   "end_xy": [
    659517.2346225941,
    4680230.8930057
   ]
  },
  "max_25m": {
   "gradient_pct": 22.66587993990106,
   "start_distance_m": 562.0,
   "end_distance_m": 587.0,
   "midpoint_distance_m": 574.5,
   "start_elevation_m": 475.4309063539059,
   "end_elevation_m": 481.0973763388812,
   "start_xy": [
    659538.140173498,
    4680244.602781096
   ],
   "end_xy": [
    659517.2346225941,
    4680230.8930057
   ]
  },
  "max_50m": {
   "gradient_pct": 20.384201760340375,
   "start_distance_m": 537.0,
   "end_distance_m": 587.0,
   "midpoint_distance_m": 562.0,
   "start_elevation_m": 470.905275458711,
   "end_elevation_m": 481.0973763388812,
   "start_xy": [
    659559.0457244017,
    4680258.312556491
   ],
   "end_xy": [
    659517.2346225941,
    4680230.8930057
   ]
  },
  "max_100m": {
   "gradient_pct": 17.482820277098313,
   "start_distance_m": 527.0,
   "end_distance_m": 627.0,
   "midpoint_distance_m": 577.0,
   "start_elevation_m": 469.2324559275103,
   "end_elevation_m": 486.7152762046086,
   "start_xy": [
    659567.4079447633,
    4680263.79646665
   ],
   "end_xy": [
    659484.5351117621,
    4680207.864536294
   ]
  }
 },
 "window_minima": {
  "min_5m": {
   "gradient_pct": -12.783715251732701,
   "start_distance_m": 702.0,
   "end_distance_m": 707.0,
   "midpoint_distance_m": 704.5,
   "start_elevation_m": 490.4531797536167,
   "end_elevation_m": 489.8139939910301,
   "start_xy": [
    659421.6649504594,
    4680167.135588142
   ],
   "end_xy": [
    659417.5880978018,
    4680164.240890851
   ]
  },
  "min_10m": {
   "gradient_pct": -11.842561249559367,
   "start_distance_m": 702.0,
   "end_distance_m": 712.0,
   "midpoint_distance_m": 707.0,
   "start_elevation_m": 490.4531797536167,
   "end_elevation_m": 489.2689236286608,
   "start_xy": [
    659421.6649504594,
    4680167.135588142
   ],
   "end_xy": [
    659413.5112451442,
    4680161.3461935595
   ]
  },
  "min_20m": {
   "gradient_pct": -10.91690640607652,
   "start_distance_m": 699.0,
   "end_distance_m": 719.0,
   "midpoint_distance_m": 709.0,
   "start_elevation_m": 490.7833884054172,
   "end_elevation_m": 488.6000071242019,
   "start_xy": [
    659424.1387446875,
    4680168.828490157
   ],
   "end_xy": [
    659407.8036514235,
    4680157.293617352
   ]
  },
  "min_25m": {
   "gradient_pct": -10.71172284752106,
   "start_distance_m": 699.0,
   "end_distance_m": 724.0,
   "midpoint_distance_m": 711.5,
   "start_elevation_m": 490.7833884054172,
   "end_elevation_m": 488.10545769353695,
   "start_xy": [
    659424.1387446875,
    4680168.828490157
   ],
   "end_xy": [
    659403.7267987661,
    4680154.398920061
   ]
  },
  "min_50m": {
   "gradient_pct": -9.613819551490678,
   "start_distance_m": 697.0,
   "end_distance_m": 747.0,
   "midpoint_distance_m": 722.0,
   "start_elevation_m": 490.96049813841046,
   "end_elevation_m": 486.1535883626651,
   "start_xy": [
    659425.8867219385,
    4680169.800382913
   ],
   "end_xy": [
    659384.9732765411,
    4680141.083312521
   ]
  },
  "min_100m": {
   "gradient_pct": -7.620349525036772,
   "start_distance_m": 694.0,
   "end_distance_m": 794.0,
   "midpoint_distance_m": 744.0,
   "start_elevation_m": 491.100631810662,
   "end_elevation_m": 483.4802822856252,
   "start_xy": [
    659428.5086878149,
    4680171.258222048
   ],
   "end_xy": [
    659346.6508615598,
    4680113.873157983
   ]
  }
 },
 "diagnostic_window_maxima": {
  "max_2m": {
   "gradient_pct": 31.99425848700912,
   "start_distance_m": 584.0,
   "end_distance_m": 586.0,
   "midpoint_distance_m": 585.0,
   "start_elevation_m": 480.2361492839441,
   "end_elevation_m": 480.87603445368427,
   "start_xy": [
    659519.7432887026,
    4680232.5381787475
   ],
   "end_xy": [
    659518.0708446302,
    4680231.441396716
   ]
  },
  "max_3m": {
   "gradient_pct": 30.05339655834594,
   "start_distance_m": 583.0,
   "end_distance_m": 586.0,
   "midpoint_distance_m": 584.5,
   "start_elevation_m": 479.9744325569339,
   "end_elevation_m": 480.87603445368427,
   "start_xy": [
    659520.5795107386,
    4680233.086569763
   ],
   "end_xy": [
    659518.0708446302,
    4680231.441396716
   ]
  }
 },
 "diagnostic_note": "Windows <=3 m are at raster-noise scale (1-sigma raster noise alone is roughly +/-7 pp at 2 m and +/-5 pp at 3 m on a 1 m DTM). Diagnostic use only: never a headline or ranking value.",
 "quality_summary": {
  "review": [],
  "extent": [
   "descends_at_start",
   "may_continue_beyond_end"
  ],
  "suggested_summit_cut_m": 693.0,
  "trailing_descent_m": 6.8
 },
 "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:26918",
  "elevation_resolution_m": 1.0,
  "elevation_tiles": [
   "data/cache/usa/ma/USGS_1M_18_x65y468_MA_Western_B24.tif",
   "data/cache/usa/ma/USGS_1M_18_x65y469_MA_Western_B24.tif"
  ],
  "calculated_at": "2026-08-24T21:34:35+00:00",
  "road_source": "OpenStreetMap (local PBF extract)",
  "road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
  "osm_pbf_path": "data/cache/pbf/massachusetts-260822.osm.pbf",
  "osm_snapshot": "2026-08-21T20:21:11Z",
  "run_id": "redo-ma-2-260824",
  "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, MA_Western_B24 (collected 2023-24)",
  "elevation_tile_ids": [
   "x65y468",
   "x65y469"
  ],
  "climb_origin": "discovered",
  "notes": "Coarse pass: max 11.7% over 200 m (Terrain 50), gain 25.6 m over 1076 m way. KEPT at seed extent: no ascending continuation (min_avg=2.0%). ADOPTED (NE wave 1, 2026-08-25): clean-steep. Wales dials per PRODUCTION 'US ADOPTION DIALS'.",
  "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"
 },
 "area": {
  "place": "Becket",
  "county": "Massachusetts"
 }
}