a dirt path leading to signal hill in saguaro national park, tucson, arizona

saguaro national park tucson mountain district arizona usa botany nature cacti vegetation outdoors spring landscape desert tourism travel adventure vacation sight solitude hiking harsh environment ecosystem rugged bucket list west america blue sky wispy clouds carnegiea gigantea ocotilla fouquieria splendens opuntia prickly pear pima county palo verde signal hill trail rocky dry scrub brush fire hazard dirt path bridge sign shadows leading