Staddle stonesYou know how the Romans built their granaries on tapered piers with a wide flat top ? That was to stop vermin being able to come in from underneath.
It works, it works well, and is worth looking at as a foundation, especially near the river and to keep vermin out.
The principle is still used....
View attachment 80927
Doesn't mean it's not a 'shed', just that it's a mouse and rat free shed.