There is a double fountain of marble in the open - air display of the Archaeological Museum of İstanbul, situated in the first garden to the left of the Çinili Köşk. This monument (inventory number 3217) was first published by A. M. MANSEL in 1931. Its lower, main body is Byzantine, carved out of a monolithe marble with two niches. The crown cut at the top is a Turkish work. The back of this small monument, which was used as a fountain during the Turkish era, is covered with a decoration in relief, which clearly shows that originally it was a Byzantine work. Here are seen the curls of acanthus leaves, coming out of a kantharos and spreading symmetrically. In the middle there is a cross, whose lateral arms were wiped off during the Turkish era. We think that the lower part, that is, the section belonging to the Byzantine era, was originally related to a water system, and most probably it was also constructed as a fountain. Though the decoration at the back, by its motif and the technique of carving, indicates the VI and VII centuries, it should be taken into consideration that this type of embellishment was used until the XIIth century. During the Turkish era, this Byzantine monument was reshaped as a Turkish fountain during the XVI-XVII centuries, as is realized from the buds of the crown at the top.