The long barrows of Wiltshire and the Cotswold areas, and the same is probably true of those in South Wales, have been thought by some Scandinavian archæologists to be closely related to the types peculiar to the Baltic region. Dr. Knut Sterjna[137] believed that the English chambered long barrows represented a stage in the evolution from the dolmens to the chambered barrows (_sépultures à galerie_) of Denmark and Sweden. The stone circles, which are conspicuous in the Salisbury plain area, are absent in France, and seem to have originated by the Baltic. It would seem, then, that some at any rate of our English megaliths were introduced, not so much by merchants coming from the south as by those adventurers who came later from the Baltic region, some of whom we have seen passed across this country to the port at Warrington. In France, too, though megaliths are more numerous and finer in the Morbihan, where we have seen that tin and gold were found, than elsewhere in that country, yet they cluster thickly in Finistère, and in a curved line from that department to the Mediterranean coast near Narbonne.[138] The occurrence of so many megaliths in Finistère and the adjoining departments may be due to the need of the early traders to take refuge in the inlets of that region, while endeavouring to round the dangerous promontory. That they did so not infrequently is shown by the occurrence near these inlets of numerous hoards of bronze implements, most of which date from the time which we are discussing.[139] The band across the country clusters most thickly just north-east of the line, running through the Carcassone gap, now followed by the _canal du midi_. This seems to indicate that a land route through the pass was in use at this time, as a safer alternative to rounding the Iberian peninsula by sea. From this line the cult seems to have spread north-eastwards, though these monuments grow scarcer the further we leave this line.