i always specify 8" of crushed stone as the main base.

a couple of inches more costs an insignificant amount. the more the better.

the romans used about 6' of stone as the base for their roads, starting with stones that probably weighed several hundred pounds each.

i drove on the appian way in rome. their roads last a long long long long time.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.