Where is the best areas to hacks round between Maidstone and ashford there is amazing countryside but where are the off road rides you can use for free?
To start with, look at the local bridleways, there should be a map on your council website. Plenty on the M20 corridor, decent riding on the north downs too.
I don't know Kent hacking too well but I'd also say, don't discount areas that run membership schemes like TROT or similiar. They really can open up some fabulous hacking routes that would otherwise be inaccessible