On the third day the fickle weather of the island became more mild and the thick white mantle of snow slowly began to release its hold on the landscape. While the legionaries welcomed the sun’s warmth, the meltwater quickly turned the track into a glutinous bog that sucked at the wagon wheels and the booted feet of the infantry. It was with some relief that they marched down the shallow incline into the Tamesis valley on the fourth day and came in sight of the ramparts of the huge army base constructed the previous summer when the legions had first forced their way across the great river. The base was now garrisoned by four cohorts of Batavian auxiliaries. The Batavian infantry had been left at the base while the cavalry squadrons patrolled up the valley, searching out and chasing off any of Caratacus’s raiding parties they might encounter. Within the base, supplies had been stockpiled all winter as the shipping from Gaul continued to cross the channel to Rutupiae whenever the weather permitted. From there, smaller barges carried provisions up the Tamesis estuary to the base that straddled the river. The final link in the supply chain was provided by small columns of wagons which made their way under heavy guard to the advance forts, manned by small detachments of auxiliary troops.

This line of defence had been erected by General Plautius to keep Caratacus at bay. A futile attempt, it had turned out. Small bodies of enemy troops regularly slipped through, under cover of darkness, to harass the Roman supply lines and wreak havoc on those tribes who had gone over to the invaders. Once in a while a more daring attack was attempted, and a handful of outposts had had their small garrisons slaughtered. Barely a day passed without some distant smudge against the clear winter sky telling of yet another attack on a supply column, native village or Roman outpost. The commanders of the auxiliary cohorts charged with defending the area could only gaze in despair at the evidence of their failure to contain Caratacus and his men. Not until spring arrived, and the weather improved, could the ponderous weight of the Roman legions be thrown at the Britons once again.