The Battle of Waterloo began at 1120 h (all times given are local) on 18 June 1815 when French artillery opened fire on the mixed British, German and Dutch forces of Wellington’s army. At the close of the day, over 47 000 soldiers had been killed or wounded, all within a horrifyingly small area of 6.5km by 3.5km (Fig. 1). Victory lay with Wellington and his Prussian ally, Field Marshal Gebhard von Blücher, and the out-come set the seal on European history for much of the nineteenth century. Yet Waterloo is not a battle in isolation, it was part of a three-day engagement that ebbed and flowed across the rolling countryside of southern Belgium.