I can't beat that at all before I moved country I was still living in the same city where most of my ancestors was from, and if not city the same county.
Me: Leeds, Yorkshire
Parents: Both Leeds, Yorkshire
Grandparents: 3 in Leeds, 1 in Barnsley, Yorkshire (about 40 mins in a car) but later moved to Leeds and married my Gran there.
Great Grandparents: 6 in Leeds, 1 in Ardsley close to Barnsley who married someone from Surrey in Doncaster (also in Yorkshire) and lived in Yorkshire until he left and his family were Navvies.
2nd Great Grandparents: 9 in Leeds, 2 in Ardsley/Barnsley, 1 in Farnham (about 30 mins from Leeds) but moved and married in Leeds to a girl from Cheshire, 1 from Suffolk but married in Leeds then later moved to Lancashire, 1 who was a navvy so born hertfordshire, married derbyshire and his wife from worcestershire.
So out of 16 Great Grandparents 12/16 always in Yorkshire (9 of whom were from Leeds), 2 who moved there (both to Leeds), and only 2 who did not.