The tumult and the shouting dies/The captains and the kings depart. And, in millions of British homes, stunned families, having switched off the recent television epic Boudica, found themselves staring at each other in disbelief. Did the Emperor Claudius really tell Boudica, "Shame to be at war all the time, isn't it?" Did the Empress Agrippina murmur post-coitally to her son Nero, "Hush, Mummy's thinking". More to the point, after two hours of this nonsense, could there ever have been that last great battle between the Queen of the Iceni and Suetonius Paulinus, the Roman governor of Britannia? Surely not, surely even that was just EastEnders long ago. The Battlefields Trust has other ideas, which is why I am walking across a field the size of a prairie in Northamptonshire with some of its members. "It has to be here," says the military historian Martin Marix Evans, who is conducting the walk. "And I'm supported in this by many people." He pauses for full dramatic effect. "Chiefly Tacitus." Suetonius chose a position in a defile, with a wood behind him. There could be no enemy, he knew, except at his front, where there was open country without cover for ambushes. Leaning on an antlered stick, white hair blowing in the wind, Marix Evans says, "There's the defile, that's where the open country was, and there are the woods." Dear God, has the man met Tacitus? "And behind us is Watling Street, it all turns on Watling Street. This is where Boudica made her last stand."