They were masters of the level country, but not of the mountains or of the sea. The west above all gave trouble to the Romans. No doubt in the extreme south-west, in what is now Cornwall, the old nationality maintained itself, probably more because the conquerors concerned themselves but little about this remote corner than because it directly rebelled against them. But the Silures in the south of the modern Wales, and their northern neighbours the Ordovici, perseveringly defied the Roman arms; the island Mona (Anglesey), adjacent to the latter, was the true focus of national and religious resistance. It was not the character of the ground alone that hindered the advance of the Romans; what Britain had been for Gaul, that the large island Ivernia was now for Britain, and especially for this west coast; the freedom on the one side of the channel did not allow the foreign rule to take firm root in the other. We clearly recognise in the laying out of the legionary camps that the invasion was here arrested. Under the successor of Plautius the camp for the 14th legion was laid out at the confluence of the Tern with the Severn near Viroconium (Wroxeter, not far from Shrewsbury);[105] presumably about the same time, to the south of it, that of Isca (Caerleon = _Castra legionis_) for the 2d; to the north that of Deva (Chester = _Castra_) for the 20th; these three camps shut off the region of Wales towards the south, north, and west, and protected thus the pacified land against the mountains that remained free. Into this region the last prince of Camalodunum, Caratacus, threw himself, after his home had become Roman. He was defeated by the successor of Plautius, Publius Ostorius Scapula, in the territory of the Ordovici, and soon afterwards delivered up by the terrified Brigantes, with whom he had taken refuge, to the Romans (51), and conducted with all his adherents to Italy. In surprise he asked, when he saw the proud city, how the masters of such palaces could covet the poor huts of his native country. But with this the west was by no means subdued; the Silures above all persevered in obstinate resistance, and the fact that the Roman general announced his purpose of extirpating them to the last man did not contribute to make them more submissive. The enterprising governor, Gaius Suetonius Paullinus, attempted some years later (61) to bring into Roman power the chief seat of resistance, the island of Mona, and in spite of the furious opposition with which he was met, and in which the priests and the women took the lead, the sacred trees, beneath which many a Roman captive had bled, fell under the axes of the legionaries. But out of the occupation of this last asylum of the Celtic priesthood there was developed a dangerous crisis in the subject territory itself; and the governor was not destined to complete the conquest of Mona. [Sidenote: Boudicca.]