The site on which the Romans founded London was the rising ground on the northern bank of the Thames, from the present Fish Street Hill, or Billingsgate, to the Wallbrook. At a later date of their occupation they extended the City eastward to the Tower, and westward to the valley of the Fleet. Then the valley of the Wallbrook divided the City into two portions of almost equal size. To the north the buildings extended to the present Aldgate and to Moorfields, and westward to Newgate and Ludgate. The wall which encompassed the town began at the Tower, and in a line with various bends in it terminated at the Arx Palatina, somewhere near the present _Times_ office. On the east of the town, where the country was flat, there was a marsh, extending to the river Lea. To the north-west were dense forests stretching far into Middlesex, and abounding with deer, wild boar, and other savage animals. This forest was partly the cause of the many brooks, which in those days watered London from the northern heights; it being a well-known fact that trees absorb and retain moisture. It is doubtful whether there were any Roman buildings west of the Fleet; Fleet Street and the Strand certainly were then undreamt of, and did not come into existence till centuries after the Romans had left our island. To the west of the present Strand, the ground lying very low, it was frequently inundated by the river, and there are persons still living who can remember Belgravia and Pimlico as a dismal swamp. Westminster Abbey stood on an island, which rose above the marshy environs, and even as late as the times of Charles II. occasional high tides converted the palace of Whitehall into an island. The great forest of Middlesex above mentioned came close to the City wall; it had, in fact, occupied a portion of the site on which the City was built, and as much of it had been cut down, and so much space cleared, as the builders required for their operations. But the nature of the forest ground could not be as readily changed. It was still full of moisture, and numerous rills continued to flow through it. Now, one of the most important of them was the Langbourne. This watercourse, so called because of its length, took its rise in ground now forming part of Fenchurch Street. It ran swiftly through that street in a westward direction, across Grass, now Gracechurch Street, into and down Lombard Street—where many Roman remains have been discovered—to the west of St. Mary Woolnoth Church, where it turned sharply round to the south and gave name to Sherbourne Lane, so termed of sharing or dividing, because there it broke into a number of rills and so reached the Thames. From this watercourse Langbourne Ward took its name. Thus says Stow, but he adds that in his day (1598) this bourne had long been stopped up at the head, and the rest of the course filled up and paved over, ’so that no sign thereof remaineth more than the name aforesaid.’