It's both higher ground and under a tree. I picked the spot because water should flow Around the entrance and not into it. He's used it before, but he definitely prefers the bush. I'll move him into the burrow sometimes and he'll either stay for a bit or leave and wander the enclosure or go back...
I appreciate your help! I'll try and do some work on the bush burrow as well. It's pretty well shaded as is but if it's going to be his preferred spot then I should probably do what I can to make it more comfortable.
I adopted a desert tortoise in April from the state of arizona. When designing the burrow I used the cinder block model and made sure to have at least 6 in of dirt all over the burrow. I have a temperature gauge inside the burrow so I know it does not exceed 90° even with it getting hotter out...