Vassiladi is located at the entrance of the lagoon and occupies a key position, controlling this entrance. This importance is also the reason for its name, with its overtones of dominance (vassilikos/king-like). Fish farms and fishermen’s huts on stilts are said to have existed there since the beginning of the 18th century. During the Revolution, the capture of Vassiladi by the Turks was of great importance for the fall of Messolonghi. It was initially attempted in 1822, but was only achieved on 25 February 1826, with large forces under Hussein Bey, who engaged in a fierce cannonade of it. Critical to the victory was the loss of all the ammunition of the defenders due to an accidental explosion, after which a general assault was successfully made by the Turks. After the events of the heroic Exodus by the garrison of Messolonghi, Vassiladi was recaptured by the British Admiral Frank Abney Hastings on the steamer Carteria on 27 December 1827.
In the lagoon of Vassiladi is the islet of Agios Sostis (or Agios Sozon), which is located about 1.5 km off from the islet of Vassiladi. It owes its name to the homonymous chapel, a pre-revolutionary building mentioned by the 17th century travellers Spon and Wheler; it was renovated in 1860. The saint is commemorated on 7 September: he is considered the patron saint of fishermen. Indeed, the chapel still remains a place of thanksgiving and prayer and houses dedications of devotees who pray or thank the saint for his protection from the dangers of the sea. There is also a stone-built lighthouse, built in 1857, 12.40 m high, and the lighthouse keeper’s house. It is a historical monument, important in the history of navigation and the study of the history of architecture. The ruins of a small fortress, built by Ali Pasha in 1805, are still preserved at Vassiladi. Its wall was about one metre wide.
Agios Sostis was the oldest port, and the main one of Messolonghi handling exports, from the end of the 16th century until 1876. It was where Lord Byron landed in 1824. It is mentioned that there was a customs office here and the goods were transported by dug-outs canoes (hewn from a tree-trunk) and by small boats out to the large ships that were docked there. Due to the shallow waters they could not approach the city any closer in than a mile and only then if they had no cargo. Post-revolutionary steamboats of the Old Steamship Company, which had a monopoly, tied up there. The ships came from Patras and arrived every Friday. There were even shelters to accommodate passengers in winter, because they might need to wait for days when strong winds blew. These are not preserved today. In the Orlofika debacle, in 1770, a naval battle took place off Agios Sostis.
