As big as you want... lol. Lots of family's will dig 1-2ft deep "pool" holes and fill it with seawater, add some shovels and toys and the little ones are occupied for hours. Or dig a 5 ft deep foxhole to combat potenial charlie lol. Either way your holes are safe here 😉
Yup, as big as you want.
Thanks! Your answer is awaiting moderation.