By the start of the new millennium most of the A3 had been dualled; of the route from Southfields to Havant, only the section that passed through Hindhead and the Devil's Punch Bowl was still single carriageway.
As the year 2000 approached, most of the A3 highway had been widened into two lanes; however, a portion of the road between Southfields and Havant remained a single lane, specifically where it traversed Hindhead and the Devil's Punch Bowl.