At Isfahan no fewer than five old bridges cross the Zendeh Rud, the most ancient being the Pul-i-Marnun, which was built by Shah Tahmasp, who reigned from 1523 to 1575. It is not a great bridge, so it stands apart from the Pul-i-Khaju and the vast Bridge of Ali Verdi Khan, which undoubtedly are among the finest bridges in the world. Their beauty has such a gracious power, such brightness and grandeur, that even the Roman bridge at Alcántara may seem to rival it unsuccessfully. Brangwyn has drawn these Persian masterpieces, but the Pul-i-Khaju alone belongs to this section on housed bridges--except in some architectural points common to both. Their arches are Moorish, and their builders may have borrowed from the Romans an idea which has come down to our time in at least one antique monument, namely, the ruined aqueduct at Lyon, not far from Saint Irénée. Through the piers of this aqueduct arches are cut transversely, so as to form a side arcade all along the length of the structure. These lateral arches vary much in size, and some of them have been built up. I know not for what purpose they were used; but they lighten the piers, which are uncommonly massive. It is this arrangement--a vaulted gallery cut through the sides of piers--that we find also at Isfahan in the two historic bridges of the Sefi kings. [Illustration: THE PUL-I-KHAJU OVER THE ZENDEH RUD AT ISFAHAN, PERSIA] The Pul-i-Khaju has been described many times, but Lord Curzon’s account of it is by far the most valuable:--