_The Road is one of the great fundamental institutions of mankind. We forget this because we take it for granted. It seems to be so necessary and natural a part of all human life that we forget that it ever had an origin or development, or that it is as much the creation of man as the city and the laws. Not only is the Road one of the great human institutions because it is fundamental to social existence, but also because its varied effect appears in every department of the State. It is the Road which determines the sites of many cities and the growth and nourishment of all. It is the Road which controls the development of strategics and fixes the sites of battles. It is the Road that gives its frame-work to all economic development. It is the Road which is the channel of all trade and, what is more important, of all ideas. In its most humble function it is a necessary guide without which progress from place to place would be a ceaseless experiment; it is a sustenance without which organized society would be impossible; thus, and with those other characters I have mentioned, the Road moves and controls all history._ _A road system, once established, develops at its points of concentration the nerve centres of the society it serves; and we remark that the material rise and decline of a state are better measured by the condition of its communications--that is, of its roads--than by any other criterion._ _The construction, the trace, and the whole character of the Road change with new social needs and habits, with the facilities of natural science, their rise and decline. But this perpetual change, which affects the Road as it does architecture and every other work of man, is specially marked by certain critical phases, one of which, as I said at the opening of this, we have now entered. There are moments in the history of the Road in any society where the whole use of it, the construction of it, and its character have to be transformed. One such moment, for instance, was when the wheeled vehicle first appeared: another when there first appeared large organized armies. It occurred whenever some new method of progression succeeded the old. It occurred at similar critical turning-points in the history of the Road not only when any of these things arose, but also when they declined or disappeared. The appearance of great cities, their sudden expansion or their decay, or the new needs of a new type of commerce--and its disappearance--bring a whole road system to one of these revolutionary points. We have had (as I shall develop in more detail)_ five _great moments of this kind in the history of the English road system: the moment when the British trackway was superseded by the Roman military road; the moment when the latter declined in the Dark Ages; the moment when the mediaeval system of local roads grew up on the basis of the old Roman trunk roads and around them; the moment when this in its turn