hilly, incline, hill, slope, switchback, downhill, downslope, steep, sidehill, undulating, upslope, unclimbable, grueling, arduous, doglegs, timberline, albula, marmolada, grossglockner, undulation, serpentine, rutted, slog, bumpy, pathless, treacherous, hairpin bend, cambered, downwind, mountain, couloir, ridge, bushwhack, kilometer, fourteener, snowfield, twisty, trail, rockface, pedaling, headwind, esses, cog railway, wanze, rutty, descents, rooty, gradient, terrain, corrie, untraveled, simplon pass, koppie, elevation, alp, slickrock, slippery, crag, chilkoot pass, hairpin, exhausting, upwind, rapids, mile, waymark, tussocky, climb, cols, gravelled, straightaways, scree, escarpment, portaged, pyrenean, lefthand, ungroomed, scafell pike, daunting, unpaved, qom, tricky, trailhead, jouncing, seracs, precipices, strenuous, hogback, donner pass, pyrenees, sprint, hucks, sastrugi, ridable, icefield, rimrock, windy, belays, obstacle, homestretch, stairmaster, diagonally, tiring, eastward, gruelling, steepest, torturous, zigzag, circuitous, onward, toilsome, fatiguing, steeper, straight, downward, perilous, southward

acclivity, ascent, climb, raise, rise, upgrade

acclivitous, ascending, hard, rising, stiff