Depending on the species and how soft the dirt or blockage is, some snakes will manage, but generally they just use holes rodents have dug.
lol, good luck with trying to stop rodents getting in... It's often completely futile. You're generally better off trying to remove the food sources before night time, they can be quite the acrobats.
I had one rat leap a meter off the top perch in an aviary to do some kind of high speed shimmy between the vertical sheetmetal of the back of the cage, and the horizontal sheetmetal of the roof. She'd do that regularly since she couldn't get in anywhere around floor level nor two meters above floor level, and it was all pointless, she had easy access to other cages containing the very same food, but just seemed to like terrorizing any chooks I tried to put in that cage. I'd blocked those holes repeatedly, with a variety of things including metal aviary mesh, rocks, bricks, wood, etc, and she just kept dragging them out of there. They're amazingly strong for their size.
Best wishes with your rodent/snake/whatever issue.