high & lofty (mountains)
崛 centers on towering height, especially of mountains: something that rises steeply and stands out prominently above its surroundings.
崛 combines 山 (mountain) with 屈, which likely contributes the sound and the idea of bending or rising abruptly, suggesting a mountain that juts up sharply.
A mountain 山 that seems to bend upward 屈, rising so steeply it looks like it's arching its back: that's a high, lofty peak.
For クツ, imagine a towering mountain so steep that climbers need special boots: boots -> クツ, and those boots help you scale the lofty heights.
standing out from the crowd; dominating; rising abruptly