A casual glance at the Celts showed that they had yet to realize the seriousness of their situation. They were doing very little; clearly they believed that the river would be a major obstacle to the Romans. They had much to learn about Rome. Gaius glanced to his right, and saw the leaders of the fourteenth viewing exactly the same scene. Mirror signals confirmed the nature of the plan Plautius wished to follow. Gaius sent a confirmatory signal, then he marched his legion towards the riverbank, in full view of the Celts. Since it was late afternoon, the Romans were beginning to establish a camp. The Celts clearly thought they were safe, as no patrols were set.
A messenger approached Gaius. This town was regarded by Plautius as important. Apparently Caratacus had heard of the intention to set up Cogidumnus as a client king, and he had sent a very sizable war party down to inflict damage and persuade that tribe not to do so. However, he had been late, and the Augusta had caught them and there had been a major battle. The Celtic war party had fled, and most of its soldiers were now in this fortified town.
The next morning the soldiers of the fourteenth were busy as only Roman soldiers could be busy. Trees were chopped down, and what were clearly pontoons and bridge sections were constructed and stood on the bank. The job of the fourteenth was to make it look as if the basic plan was to launch a frontal attack across the river. The twentieth was doing something similar upstream, also in view of the Celts, however Gaius also sent three cohorts under the command of Falco upstream, where they would cross the river out of sight of the Celts. Thus while on the eastern side of the river everything seemed chaotic, the following day was designated for the attack. Gaius also called Lupus to his tent, and told him that he would have the honour of leading the river crossing. He was pleased to see that Lupus, while recognizing the seriousness of the orders and the risks, was also pleased that he had been chosen, and he promised that his cohorts would secure a position on the other side of the river.
Before first light, Plautius despatched his Batavians. These soldiers were able to swim rivers fully armed, and when they emerged on the other side, their arrival was unseen by the Britons. They crept to the rear of the enemy camp, and in the early light of predawn they set about disabling or stealing the horses. Without horses, the Celtic chariots were useless. Not that this land was ideal for chariot deployment.
Across the river, Gaius smiled when he heard the cries from the furious Celts. A number of them immediately began chasing horses, Batavians, anything. That lack of discipline would always tell against them. Of course they could chase the Batavians, and at first sight this seemed a cost-free option of exacting some cost from the Romans. It was not.
The previous night a cohort under the command of Gaius Hosidius Geta had made a night crossing near the river mouth. Now was the time to emerge. Plautius had ordered it to provide a further distraction to allow the Batavians to get further away, but Geta did more, by launching his small force at the rear of the pursuers. Suddenly the chasers found themselves isolated, dispersed, and caught in a pincer between the two small forces. The angry Celts flung themselves furiously on the Romans, but after the first blows they found themselves being driven relentlessly backwards by the shield wall. The angry Celtic battle cries gradually gave way to Celtic swearing, and cries of Celtic pain as the hob-nailed Roman boots were driven brutally into the ribs of Celtic wounded lying on the ground.
A further detachment of Celts emerged from the main fort, and rushed to help. Geta ordered the horn blast, and apart from the line immediately fighting Celts, his whole cohort reversed, and drove into the new attackers. Someone in the Celtic camp must have decided that this fighting in the open was fruitless, and a Celtic retreat was ordered.
The Celts turned and, with varying degrees of speed, retreated. Geta's men pursued as fast as they could, back-stabbing the slow, until they reached the first of the fortified gates, which were slammed shut just before the last of the Celts could regain safety. As the sounds of reinforcing beams could be heard being placed into position to hold the gates, the few remaining Celts had to face the charging Romans.
Without thinking, the front line of the Romans charged the Celts, only to be struck by a barrage of huge rocks from above. Quickly the order was given to lock shields above, but now the small Celtic party surprised by attacking, swinging their large heavy swords at the Roman legs. Blow after blow landed, and Romans began fall to the ground, legs bleeding profusely.
Then suddenly another band of Celts emerged from another gate, and launched themselves furiously on the Romans. Even Geta himself had to take a sword and shield and personally join the line. He signalled the retreat, and gradually the cohort pulled back from the wall. As they got further away, those behind the wall could only help their comrades with arrows. Still the blows were traded, and since the Romans could not force the Celts with their shields for fear of the arrows, the Roman losses were still significant.
Then the Celtic commander ordered the retreat. The Romans did not attempt to follow. As Gaius was to remark later, this was a significant lost opportunity for the Celts; if they did not feel confident of defeating one cohort that was clearly in trouble, there was not much point in attempting to fight two legions.
It was now time for the twentieth to make a more public and direct crossing. Gaius sat on his horse on a rise as he watched Lupus marshal his troops onto the rafts that had been made the previous evening, and cross in full view. The Celts saw the rafts and began hurling insults. As an attack, this seemed destined to fail, and the Celts became more derisive by the minute, particularly as the rafts apparently could not even keep on the proper course, but instead seemed to be drifting downstream of the main camp. Then, just as the Celts began to hurl their first spears, a horn signal could be heard.
From the rear of the Celt's camp, fearful yells could be heard and the Celts turned to see the first advance of Falco's men. Meanwhile, Geta's men had reformed, and were marching to cut off attempts at fleeing from the fortifications. Now, the Celts found that instead of defending behind a river the opposition had to cross, they were encircled by the Romans. In the general confusion, the Celts seemed not to notice that the rafts had now purposefully driven into some marshes.
At first Gaius had a sinking feeling that he had misjudged, for the men began jumping off rafts. He felt so helpless, being on the wrong side of the river. He should be there, where he could. . But no, he realized that he had to trust the Centurions and Lupus. He was not essential everywhere, and he was too valuable to risk being killed on a failed landing. Not that it would fail, but there had to be the possibility of failure. All he could do was watch, as the soldiers with their heavy armour quickly began floundering in the deep mud, and as they tripped over reeds it became almost impossible to maintain their shields in locked formation. It was then that he saw Lupus quickly grab a long pole and push for all he was worth; his raft continued, and when two legionnaires saw what he was doing they grabbed the pole from him. With muscles straining they pushed, driving the raft closer to the ground, other soldiers using their shields to form a protective wall.
But eventually the raft could go no further. An Optio more experienced with marshes leaped forward, shield ahead, and advanced with the slow stride that made it easier to stay on his feet. The men followed, several falling flat on their faces as they tried to catch up. The Optio turned and called for the men to do what he was doing, then he fell back, to allow the shields to advance and for the protective wall to form. But as men fell into muddy holes, the long shield became a hindrance, and while they were struggling, Britons would appear from nowhere, throw spears, then disappear equally quickly.