How each climb is scored: - Steepness × length (64%) — feet gained per mile, boosted by distance with diminishing returns (short steep punches matter less than long sustained grinds) - Exposure (18%) — how open/above treeline the climb is, sampled from satellite land cover data - Pack weight (18%) — how far to the next resupply in your hiking direction, at 2 lb/day × 20 mi/day pace To qualify as a climb: - At least 200 ft gain, 1.5–40 mi long, averaging 100+ ft/mi - No more than ~100 ft of downhill mid-climb (otherwise it's two climbs) - Flat trail-in miles before the grade kicks in don't count toward difficulty - Ties/overlaps: if two detected climbs cover mostly the same ground in the same direction, only the one with more gain is kept.