In the ancient city of Dyrrhachion (modern Durrës), a rescue excavation undertaken in an area close by the “Sh. Mazreku” school, revealed the remains of a tower that is thought to be part of the late antique fortification (early Byzantine). Close by the tower was discovered a section of the sanitarian channel of the late antique city. The tower is partly preserved and it has an irregular shape plan. The maximum tower width is 10, 80 m and its thickness varies from 3, 40 m to 3, 80 m. The foundation is made of irregular stones and mortar while the facade is with parallelepipeds tufa stones. In the inner part of the foundation wall are also incorporated fragments of tiles. Above the walls, in individual parts are preserved 5 to 10 lines of tiles (measuring to: 36 x 0. 34 x 0.045m; 0. 44 x 0. 32 x 0.045m) bonded with solid mortar. This tower is part of the northern side fortification system of Byzantine Dyrrachium and belongs to the second enclosure of the 6th century defensive system. The drain is built parallel with the surrounding wall line, about 5 – 6 m away from the outside part the curtain. The stretch discovered is 20 m long, 1. 70 m wide and 1. 05 high. The upper part of the channel vault was badly damaged. Its foundation was of stones and solid mortar while the lateral sides and the vault were of tiles (of different dimensions; 0.35 x 0.27 x 0.045m; 0.37 x 0.29 x 0.049m) and mortar. This building technique is similar to that of the Byzantine tower. The materials founded around the tower and the drain is represented by: Aegean amphorae of LRA1 and LRA 2 types; African (spathion type), Keay 62 type, amphoras of Gaza, etc. There are other finds which are fewer in number: Aegean jugs, unidentified type of jugs, African terra sigilatta, Phocean sigilatta, etc. The pottery found in this layer dates from the end of the 4th century A.D, up to the beginning of the 7th century A.D.