A glance at a map of the British Isles will show you that Cheshire lies in the very heart of the three kingdoms. Its geographical position has thus made it a meeting-place of nations, and you will see in later chapters that all the peoples that have helped to make our national history have in turn realized the importance of its position, and have fought desperately for its possession. Briton and Roman, Angle and Saxon and Dane, Welsh and Norman have all left some mark of their presence in the county, and from these many elements is derived the blood that flows in the veins of nearly all Cheshire boys and girls of to-day. Now look at the map opposite. The shaded portions represent land over 300, 600, or 1,000 feet above sea-level. In the south, the eastern and western uplands slope gradually down towards the bit of white which touches the centre of the bottom of the map and forms what is known as the Cheshire Gap. Through this gap the Midlands lie open to the north-west and to the Cheshire Plain, and over these lower heights naturally passed the great highway from London to the Irish Sea. Chester, built on a rocky plateau at the head of the tidal waters of the Dee and protected on its western side by a natural bend of the same river, was clearly a position of great importance for guarding alike the coast road into North Wales and the roads to the north of England; and there is no doubt that it was held as a fortified post long before the Romans built the Roman city of Deva. For many centuries this stronghold was one of the chief military outposts and frontier towns of England, not often free from war's alarms, and the sentinels on her walls and watch-towers ever on the look-out for the approach of some new enemy. Chester became the 'base' or head-quarters from which all military campaigns in the north-west, in Wales or in Ireland were carried out, united with the metropolis by the great road that passed through the heart of England, along which armies could march without any difficult hills to cross and hardly a river of any great size to bridge. In later and more peaceful times, for the same geographical reasons, the London and North-Western Railway, the lineal descendant of the ancient 'Watling Street', laid its lines on nearly the same ground as the old highway, and is thus the easiest as well as the most direct of all routes from London to the north-west. [Illustration: CHESHIRE CONTOUR MAP]