However, a complete detailed study of the highways of the early Indians according to this method will not be indulged in for certain respectable reasons; there are very few undoubted routes of the mound-building Indians, and a detailed comparative study of these and later Indian routes would become, under the circumstances, too speculative to be of genuine historical value. Our purpose, then, will be, merely to give the reasons for believing that the earliest Indians had great overland routes of travel; that, though they lived largely in the river valleys, their migrations were by land and not by water--in short, that these first Americans undoubtedly marked out the first highways of America used by man, as the large game animal, the buffalo, marked out the first great highways used by animal life. These highways were the highestways because their general alignment was on the greater watersheds: and our study may be better described perhaps by a subtitle--a study in highestways. CHAPTER II DISTRIBUTION OF MOUND-BUILDING INDIANS The mounds of these first Americans of which we know are found between Oregon and the Wyoming valley, in Pennsylvania, and Onondaga county in New York; they extend from Manitoba in Canada to the Gulf of Mexico. The great seat of empire was in the drainage area of the Mississippi river; on this river and its tributaries were the heaviest mound-building populations. Few mounds are found east of the Alleghany mountains. In the _Catalogue of Prehistoric Works East of the Rocky Mountains_, issued by the Bureau of Ethnology of the Smithsonian Institution,[5] the geographical extent and density of the mounds in central North America is brought out state by state with striking suggestiveness. While the layman is warned that these maps "present some features which are calculated to mislead," and that the maps indicate "to some extent the more thoroughly explored areas rather than the true proportion of the ancient works in the different sections," still some conclusions have already been reached which future exploitation will never weaken. It is not expected that future investigation will change the verdict that the heaviest mound-building population found its seat near the Mississippi and Ohio rivers. "There is little doubt," writes Dr. Thomas, "that when Mississippi, Alabama, and Georgia have been thoroughly explored many localities will be added to those indicated ... but it is not likely that the number will be found to equal those in the area drained by the Ohio and its affluents or in the immediate valley of the Mississippi."[6] This fact, that the heaviest populations of the mound-building Indians seem to have been near the Mississippi and Ohio is, of course, shown by the archæological maps. In a rough way, subject to the limitations previously mentioned, it can be found that the following fourteen states contain evidences of having held the heaviest ancient populations: