The district associated with the Church of St. Mamas (Zonaras, xvi. c. 5, ἐν τῇ κατὰ τὸ Στενὸν τοποθεσίᾳ τῇ τοῦ ἁγίου Μάμαντος καλουμένῃ) must have occupied the valley which extends from the Golden Horn southwards to the village of Ortakdjilar, the territory between Eyoub (Cosmidion) and Aivan Serai at the north-western angle of the city. The church itself, with its monastery (Cantacuzene, iv. pp. 107, 259), stood, probably, on the high ground near Ortakdjilar. Owing to its charming situation, the suburb was a favourite resort, and boasted of an Imperial palace, a hippodrome, a portico, a harbour, and, possibly, the bridge across the Golden Horn. The indications for the determination of the site of the suburb are: (1) it stood nearer the Golden Horn than the Gate of Charisius did; for in the military demonstration which Constantine Copronymus made before the land walls, against the rebel Artavasdes, by marching up and down between the Gate of Charisius and the Golden Gate, the emperor reached St. Mamas and encamped there, after passing the former entrance on his march northwards (Theophanes, pp. 645, 646). (2) The Hippodrome of St. Mamas was in Blachernæ (Ἐν Βλαχέρναις ... ἐν τῷ ἱππικῷ τοῦ ἁγίου Μάμαντος—Theophanes, p. 667), a term which could be used to designate even the district of the Cosmidion (_Paschal Chron._, p. 725, τὴν ἐκκλησίαν τῶν ἁγίων Κοσμᾶ καὶ Δαμιανοῦ, ἐν Βλαχέρναις). (3) The suburb stood near the Cosmidion; hence the facility with which the Bulgarians under Crum were able to ravage St. Mamas from their camp near the Church SS. Cosmas and Damianus (Theophanes Cont., pp. 613, 614). (4) The suburb was near the water; for it had a harbour (Theophanes, p. 591). It is also described as situated on the Propontis (Genesius, p. 102), on the Euxine (Theophanes Cont., p. 197), on the Stenon, the Bosporus (Zonaras, _ut supra_), these names being applied in a wide sense. (5) At the same time the Church of St. Mamas stood near the walls (Zonaras, xiv. p. 1272, πλησίον τοῦ τείχους), and near the gate named Porta Xylokerkou (Cedrenus, i. p. 707). This does not necessarily imply that the church was immediately outside the gate, but it intimates that the church was at no very great distance from the gate, and could be easily reached from it; as, for example, the Church of the Pegè stands related to the Gate of Selivria (see above, p. 73). Such language would be appropriate if a branch road leading to St. Mamas and the Golden Horn left the great road, parallel to the walls, at the point opposite the Porta Xylokerkou.