山 depicts three peaks rising in a row. As radical it locks 峰 into the mountain family alongside 岭岩岸, telling readers immediately that this character refers to something high and rocky.
夆 supplies the sound (féng drifted to fēng). The same phonetic powers 蜂锋烽逢, all sharing the feng reading. Faint semantic flavor of converging shapes hints at the pointed apex where slopes meet — the summit.