The traffic in olives and olive-oil is very considerable at Salon; indeed, one may say that it is the centre of the industry in all Provence, for the olives known as “Bouches-du-Rhône” are the most sought for in the French market, and bring a higher price than those of the Var, or of Spain, Sicily, or Tunis. Not far from the northern shores of the Étang de Berre, just above Salon, runs the great national highway from Paris to Antibes, branching off to Marseilles just before reaching Aix-en-Provence. The railway also passes through the heart of the same region; but, in spite of it all, only few really know the lovely country round about. The region is historic ground, though in detail it perhaps has not the general interest of the Campagne d’Arles or Vaucluse; still it has an abounding interest for the traveller by road, and nowhere will one find a greater variety of topography or a pleasanter, milder land than in this neglected corner of Provence. The roads here are flat, level stretches, five, ten, or more kilometres in length, and are as straight as an arrow. There is a kilometre stretch just west of Salon that the Automobile Club de France has adjudged to be perfectly level, and there a road-devouring monster of 200 h.p. recently made a world’s record for the flying kilometre of 20¾ seconds. [Illustration: _The Kilometre West of Salon_] Before returning to the shores of the Étang de Berre, one should make a détour to Roquefavour and Ventabren. One finds a complete change of scene and colouring, quite another atmosphere in fact, and yet it is only a scant ten kilometres off the route. The château and aqueduct of Roquefavour are each a sermon in stone, the latter one of those engineering feats of modern times, which, unlike wire-rope bridges and sky-scrapers, have something of the elements of beauty in their make-up. Near by, on a rocky promontory, with a base so firm that all the winds of the four quarters could never shake its foundations, is the significantly named village of Ventabren. All about are the ruins of the magnificence which had existed before, somewhat reminiscent of Les Baux, while beneath flows the river Arc, the alluvial soil of whose bed has proved so advantageous to the vine-culture hereabouts. The aqueduct of Roquefavour has not had the benefit of six centuries of aging possessed by that similar work near Nîmes, the Pont du Gard of Agrippa; but it harmonizes wonderfully with the surrounding landscape, in spite of the fact that it is only a mid-nineteenth-century work, built to conduct water to Marseilles from far up the valley of the Durance. Overhead, and beneath the ground, for 122 kilometres, runs the canal until here, where it crosses the Arc, the monumental viaduct has proved to be a more stupendous work than any undertaken by the Romans, who, supposedly, were the master builders of aqueducts.