At the foot of the hill by the mouth of the River Cottone was the East Port, which was more than 600 metres wide on the inside and was probably equipped with a mole or breakwater to protect the acropolis. It underwent changes in the fourth and third centuries: it was enlarged and flanked by piers (oriented north-south) and by storage areas. Of the two ports of Selinus, which are both now silted up, the West Port on the River Selinus-Modione was the main one.