I was looking at an Ebay Item J.R.R. TOLKIEN ~ COMPLETE UNWIN HYMAN CATALOGUE 1989/90 and was intrigued by the entry on this page http://www.mjtbooks.com/images/ebay/jrrtcat08.jpg

There are two maps in packs of six, does anyone know what these maps looked liked, and why were they sold in packs of six?