What year did Paul Simon write 'Homeward Bound'?

Paul Simon wrote "Homeward Bound" on the platform of Widnes railway station after a small tour of the UK in the late 60s. Widnes used to be part of Lancashire but is now part of Cheshire (the county boundaries changed during the early 70s), Britain, England (the North West, midway between Liverpool and Manchester, near Runcorn and Warrington). There is a small sign posted on the rail house wall.