Another vote for Worthing. I was 15 years old when I wrote to my MP about the bypass proposals as a school project. I'm 47 now.
Loads of houses alongside the existing single carriageway were compulsory purchased in the 90s, sat empty for years and then sold back to the public.
The whole A27 is completely overwhelmed by traffic. It often takes me over an hour to get to work in Brighton - 12 miles away.
If they can tunnel through solid rock in Italy, I really don't understand why we can't tunnel under the chalk of the South Downs...