last ing ▁snow ▁patch es . ▁▁ ▁The ▁Mon ad h li ath ▁mountains ▁lie ▁to ▁the ▁north ▁of ▁Str ath spe y , ▁and ▁compr ise ▁a ▁ble ak , ▁wide ▁plate au ▁rising ▁to ▁between ▁ 7 0 0 ▁and ▁ 9 5 0   m . ▁ ▁Two ▁major ▁transport ▁routes ▁run ▁through ▁the ▁park , ▁with ▁both ▁the ▁A 9 ▁road ▁and ▁the ▁High land ▁Main ▁Line ▁crossing ▁over ▁the ▁Pass ▁of ▁Dr um och ter ▁and ▁running ▁along ▁Str ath spe y , ▁providing ▁links ▁between ▁the ▁western ▁and ▁northern ▁parts ▁of ▁the ▁park ▁and ▁the ▁cities ▁of ▁Per th ▁and ▁In ver ness . ▁The ▁High land ▁Main ▁Line ▁is ▁the ▁only ▁main line ▁rail ▁route ▁through ▁the ▁park , ▁however ▁there ▁are ▁several ▁other ▁major ▁roads , ▁including ▁the ▁A 8 6 , ▁which ▁links ▁Str ath spe y ▁to ▁Fort ▁William , ▁and ▁the ▁A 9 3 , ▁which ▁links ▁the ▁De es ide ▁area ▁of ▁the ▁park ▁to ▁both ▁Per th ▁and ▁Aber de en . ▁ ▁Ge ology ▁ ▁The ▁majority ▁of ▁the ▁rocks ▁within ▁the ▁C air ng orm s ▁National ▁Park ▁belong ▁to ▁the ▁Dal rad ian ▁Super group , ▁a ▁thick ▁sequence ▁of ▁s ands , ▁mud s ▁and ▁lim est ones ▁that ▁were ▁depos ited ▁between ▁about ▁ 8 0 0 ▁and ▁ 6 0 0 ▁million ▁years ▁ago ▁on ▁the ▁marg ins ▁of ▁the ▁former ▁continent ▁of ▁Laurent ia . ▁Ro cks ▁now ▁as cribed ▁to ▁the ▁Mo