I've taken the corn snake out in the yard in good weather. He seems to appreciate the opportunity to stretch, climb walls and tree trunks. I watch him like a hawk, however, and do NOTHING else when he is out cruising. Yeah, they are so fast. He is a light pink morph, so easier to find than most. I'd never risk that with the Sonoran Gopher...the Call of the Wild...she would take off at speed, and be gone in the blink of an eye.
I'd really like to make an out-door completely enclosed pen with hardware cloth for them to hang out in and get some real exercise. One alternative I thought of was a large tent, with the rain fly off. I actually bought a very large tent at the local thrift shop, and all the zippers were secure; it would have worked well. Unfortunately, it was missing missing a couple of those collapsible poles, and I didn't want to deal with the headache of trying to source some pricey new ones that were the correct length.