If you like grand mountains, here in Couserans is Mont Vallier, a superb giant of the central chain of the Pyrenees. If it is sweet sloping valleys that you prefer, here they are in all their unspoiled wildness, for the railway actually does stop at St. Girons. If an ice-cold mountain stream would please your fancy, there is the Salat and its tributaries, flowing down by St. Girons and St. Lizier into the Garonne. And, finally, if you wish to roll back the curtain of time you will see in old St. Lizier a stage set with the accessories the reminiscent splendours of which will be scarcely equalled by any other feudal bourg of France. There is no region in the Pyrenees of which less is known historically than the Valley of the Salat. A vicomte reigned here in the sixteenth century, but the seigneury was divided among different branches of the family soon after; and, if they had an archivist among them, he failed to preserve his documents along with the written history of the greater affairs of Toulouse and Foix. Soon religious and civil troubles began to press and much of Couserans gave allegiance to neighbouring feudalities, with the result that from the times of Henri IV to those of the Revolution, not an historical event of note has been chronicled. As one approaches St. Girons, the metropolis of the Couserans, by road from Foix, he passes through the Grotto of the Mas d'Azil, a great underground cave, through which runs a splendid carriage road. It is a work unique among the masterpieces of the road builders of France. This subterranean roadway has, perhaps, a length of half a kilometre and a width of from ten to thirty metres. It is not a stupendous work nor an artistic one, but a most curious one. This Grotte de Mas d'Azil with its great domed gallery can only be likened to a Byzantine cupola. This much is natural; but a roadway beneath this noble roof and a parapet alongside are the work of man. It gave shelter to two thousand persons under its damp vault during the wars of religion, in 1625, when the neighbouring Calvinists here defended themselves successfully against the Catholic army of invaders. The cavern was practically a fortress, then, and an old atlas of the time shows its precise position as being directly behind a little fortified or walled town, the same which exists to-day. The roadway on this old map was marked, as now on the maps of the État-Major, as running directly through the "Roch du Mas," and an engraved footnote to the plate states that the "_rivière passe dessoubs ceste montagne_." When Richelieu triumphed against the Protestants he razed the fortifications of Mas d'Azil, as he did others elsewhere. The little town is really delightfully disposed to-day, and has a quaint, old domed church and a fine shaded promenade which would make an admirable stage-setting for a mediæval costume play.