Places to ride in Mariposa California

[Red Ryder]

There is a 147 acre motocross park on Old La Grange Rd.. Fortunately it is 11 Mi. from my house, well sort of, I'm about to move there anyway. Does anyone know if it's a good place to ride? And is there anywhere around mariposa, La Grange, Jamestown, Culterville?

Thanks,
Jordan