usa, arizona, sunset crater volcano national monument

america ancient archaeological arid arizona ash basalt beautiful black bonito bushes cinder clouds cone countryside crater desert dormant erupt eruption exterior fall famous field fissure flagstaff flow forest francisco geo geologic geology hiking hill horizon inactive land landmark landscape lava lavarock monument moon mountain mountains national natural nature old outdoor outdoors park peak pine rock rural san sands scenery scenic service southwest state stone texture trail travel tree trees unique usa volcanic volcano