The Porticciolo of the marina of Piombino, situated close to Porta a Mare, served for the town’s shipping activities. In 1247 a fountain was added – the Fontana della Marina or the Fonte dei Canali (also known as the "Serpi in amore" because of the fountain’s bas relief decorated with two serpents) – which supplied drinking water for the population and embarking ships. During the second half of the 15th century the Porticciolo was modernized by Jacopo III. In 1466 a tarsinata or sheltered dock large enough to receive a galley was built for the use of the Signore and to berth merchant ships. To enhance the defenses of this modest port, in 1471 it was decided to construct a tower (which has since been dismantled). During his visit in 1504 Leonardo studied the harbour’s site and noted that it was the only weak point along Piombino’s coast as its defenses were entirely insufficient. In the Codex Madrid II there is a drawing of an urban port complete with a fortified bastion and tower, which were supposed to replace the Porticciolo.
Piombino’s port was refurbished more than once over the centuries, but the tarsinata retains its aspect of a traditional fishing port.