Cabeza Prieta National Wildlife Refuge, AZ / Cottontop cactus (Echinocactus polycephalus) with the Cabeza Prieta Mountains in the background at sunset. 42001H8

Cabeza Prieta National Wildlife Refuge, AZ / Cottontop cactus (Echinocactus polycephalus) with off-road vehicle tracks cutting through the desert. 32001V1