But perhaps the most interesting of all the Roman remains are the two or three fragments of the great wall, which was not built till somewhere between the years 350 and 365 A.D. At this time the Romans had been in occupation for several hundred years, and the city had spread quite a distance beyond the old citadel walls. The new wall was a splendid one, twenty feet high and about twelve feet thick, stretching for just about three miles. It ran along the river front from the Fleet River to the corner where the Tower stands, inland to Bishopsgate and Aldersgate, then across to Newgate, where it turned south again, and came to the River not far from Blackfriars. Several fine sections of the ancient structure can still be seen in position. There is a large piece under the General Post Office yard, another fine piece in some wine cellars close to Fenchurch Street Station, a fair piece on Tower Hill, and smaller remnants in Old Bailey and St. Giles’ Churchyard, Cripplegate. [Illustration: BASTION OF ROMAN WALL, CRIPPLEGATE CHURCHYARD.] What do these fragments teach us? That things were not all they should be in London. Instead of being built with the usual care of Roman masonry, with properly quarried and squared stones, this wall was made up of a medley of materials. Mixed in with the proper blocks were odd pieces of buildings, statues, columns from the temples, and memorials from the burying grounds. Probably the folk of London, feeling that the power of Rome was waning, were stricken with panic, and so set to work hurriedly and with such materials as were to hand to put together this great defence. Nor were they unwise in their preparations, for danger soon began to threaten. From time to time there swooped down on the eastern coasts strange ships filled with fierce warriors—tall, fair-haired men, who took what they could lay their hands on, and killed and burned unsparingly. So long as the Roman soldiers were there to protect the land and its people, nothing more happened than these small raids. The strangers kept to the coasts and seldom attempted to penetrate up the river which led to London. But these coast raids only heralded the great storm which was approaching, for the daring sea-robbers had set covetous eyes on the fair fields of Britain. CHAPTER THREE _How the City grew_ (_Saxon Days_) In the year 410 the Romans were compelled to leave Britain. Troubles had become so great in Rome itself that it was necessary to abandon all the outlying colonies to their fate. From that moment began a century and a half of pitiful history for our country. There was now no properly drilled army to ward off attacks; and the raids of the “sea-robbers” increased in number and intensity. Saxons, Angles, and Jutes, they came in vast numbers, gradually working their way inland from the coast.