Last site to visit that relates to the initial Somme battles was Lochnagar crater, which is from one of the mines detonated prior to the first attacks. Unlike those at Messines this one does not hold water and you can see how huge it really is. Would like to fall in it let alone be above it when it went off. You can see the Airbus airport outside of Albert (this is where all their planes are put together after being built all over Europe) from here and we watched one of their huge delivery planes take off.