Near Phoenix

Greetings. I am travelling to Phoenix for a few days, and after work is
done I will have about 6 hours on Sunday to drive somewhere scenic and
back. Not much time I know. Ideally I'd like to see some of the desert
(I've never been to that part of the States) and get out and hike around
or scramble up something for fun. Any ideas on what to visit will be
greatly appreciated --I'd very much like to keep the drive time down to no
more than 3, 3-and-a-half hours so as to get outside a bit (it's cold
where I live, I want to feel the warm sun!)

Bye --Ian