Major and Mrs Holt's Battlefield Guide to the Somme now in its Fourth Edition is the most comprehensive guide available to the battlefields. Historical background is accompanied by detailed itineraries explaining what there is to see, what happened where, where the museums, memorials and cemeteries are as well as tales of valour and courage. Tourist details are included too with details of local tourist offices.
There are 288 pages and 258 colour pictures as well as an accompanying separate full-colour map of the battlefield area..

Martin and Mary Middlebrook, The Somme Battlefields ; this gives details of all sites with cemeteries, memorials, preserved trenches, etc., covering British, French and German elements & First Day on the Somme.

Rose Coombs Before Endeavours Fade, on the military cemeteries of the First World War ; first published in 1976 but updated recently is still a very useful and heavily illustrated companion to touring the battlefields ;

Anne Powell, A Deep Cry, a biographical and literary guide to poets and other writers who were killed on the Western Front during the First World War ; it includes many names of men killed in the Somme department ;

The Michelin Green Guide to Picardy ;

John Giles, The Somme then and now