Devizes is right in the middle of the northern part of Wiltshire.
It's about 2 hours drive from London via the M4/A4 or M3/A303
From Bristol its about 1 hour.
There are regular coaches from London & Bristol.
Although Devizes does not have a railway station there is a regular train service from most of the train stations in a 10-15 mile radius from the town.