This, standing at an elevation of 9,100 feet, is one of the dreariest of places, being situated in a desert, and consisting merely of the station and a hotel. Beyond the Bridge there is no object of interest and it is not necessary, perhaps, to speak of the hotel. The Bridge[142] itself has a commonplace appearance, but it is an extraordinary natural phenomenon. It appears to be a natural dam of earth and rock lying athwart the Cuevas River, which has managed to bore a passage through the barrier. The stones, earth, and shingle which compose the arch have been cemented together by deposits from the hot-springs, and the Bridge is 66 feet high, 120 feet wide, and 20 or 30 feet thick. Underneath the vaulted arch there bubble up springs of very high temperature, and the most striking feature here is the glittering and jagged masses of stalactite which adorn the grotto. The baths are considered to have great medicinal value, and there is a variety called the champagne bath which all arrivals are urged to take. In course of time Puente del Inca will no doubt be a much-frequented health resort, and there would not be the slightest difficulty in obtaining from the perennial river sufficient water to make a pretty town with trees and flowers, but it could never be a place of any natural attractiveness owing to the poverty of the scenery. Nobody seems to know why it should be called the Inca's Bridge; probably the name merely illustrates the tendency of simple people to attribute strange natural phenomena to the most powerful active force with which they are acquainted. Our rustics invariably attribute such things to the Devil. [Illustration: PUENTE DEL INCA.] However, the climate is cold and bracing, and the walk--some 10 miles--to Las Cuevas, up the valley and over the pass, is worth taking. There is, of course, nothing to see on arrival but some tin huts, and there is nothing to do but return on foot or by train to Puente del Inca and long for the train to Valparaiso. This calls only on alternate days. The journey up the valley is renewed and the train slowly makes its way to Las Cuevas. Here the traveller has the opportunity, which he will soon lose, of riding over the Andes. The line comes to an end at Las Cuevas, until it is linked up with that of Chile by the completion of the permanent way. Here it may be well to advise the traveller to provide himself at Mendoza with a supply of Chilian money, for, though the railway officials are ready and anxious to change English sovereigns into the grimy notes of Chile, their estimate of the Chilian dollar is apt to be of a highly optimistic character, which is rarely borne out by the rate of exchange.