Opinions have differed as to whether the ancient road ran, like the modern highway, between the salt-pools and the sea, or skirted the foot of the hills, making a circuit round the pools. In any case it seems probable that in antiquity the water of the salt-springs was not dammed up as at present so as to form pools, but was allowed to flow directly into the sea in brooks which hence received the name of Rhiti (‘streams’). After entering the Thriasian plain the road continues to skirt the shore. As the ground is here low and marshy, the road is raised on a causeway, which consists of ancient materials mixed with those of later ages. This causeway therefore marks the line of the Sacred Way. On the right of it, about half a mile beyond the salt-pools, where the road to Kalyvia branches off across the plain to the right, there are remains of an ancient monument, which appears to have consisted originally of a cubical mass of earth, cased with white marble and supporting a tombstone. An inscription proves that the monument marked the tomb of one Strato, his wife Polla (Paula) Munatia, and his son Isidotus. This sepulchre, one of the many sepulchres which lined the Sacred Way in antiquity, is not mentioned by Pausanias. The Thriasian plain, through which the Sacred Way led to Eleusis, is surrounded by mountains and hills except on the south, where it is bounded by the Gulf of Salamis. It is about nine miles long from east to west, and five miles wide at the broadest part, from north to south. The northern and western parts of the plain are stony and barren. Nearer the sea there is a tract of fertile cornland, but it does not extend much to the north of Eleusis itself. The monotony of the otherwise treeless expanse is broken here and there by some scattered olive-trees and oaks. In spring and early summer the plain is gaily carpeted in places with anemones, red, purple, and blue.