Not wishing to detract from the song at all but the phrase "The Rossendale" doesn't sound right to me as the area is always refered to just as Rossendale.

The river is the Irwell and the area name is derived from the "Forest of Rossendale", its medieval name, and applies to the complex area of hills.

The area is composed of several smaller valleys with tributaries to the Irwell running down them.

If you look at the chronological sequence of transport routes in the area you will find that the old ones ran high up the slopes and on the ridges. The toll roads were built lower down and the modern ones lower still, along with the railways. The towns also tend to have the older parts higher than the newer parts. There was a very small population before the late eighteenth century, St James's church Haslingden, being one of the oldest sites, hence the name Newchurch for the later hamlet nearer to Rawtenstall.

Many of the older buildings in Rossendale have now been demolished, along with the mills.