Considered by Paul Simon to be the best song he ever wrote.
According to an article in the London Times, this is an account of Paul Simon's marriage break-up with his first wife Peggy Harper. The nine-year-old "travelling companion" he refers to is their son Harper, who three years later, at the age of 12 accompanied his father on the Graceland tour. (Source Graceland Songfacts).
The Mississippi Delta was shining
Like a national guitar
I am following the river
Down the highway