The ongoing attacks by the pirates of Agia Mavra provoked a strong response from the Republic of Venice. In order to suppress the pirate activity around Lefkada, they sent their fleet led by the commander-in-chief Francesco Morosini, who arrived at the castle with a force of 10,000 men on July 21, 1684. He immediately began the siege with a fierce bombardment of the northern and western walls, which were more vulnerable due to their thinness. To cut off the water supply of the besieged, he destroyed part of the aqueduct. The explosion of a powder magazine near the western wall caused a large section to collapse, through which the besiegers entered, thus leading to the capitulation of the Ottoman forces. The castle’s surrender treaty was signed between Morosini and Bekir Aga, the fortress commander. It provided for the safe transfer of the Ottomans to Preveza. However, it excluded the 600 pirates who were executed on the spot, following the Venetian Admiral’s orders.
After the siege, the three Islamic mosques that had been constructed within the castle were converted into Christian churches. The Pasha’s mosque was transformed into a Catholic church dedicated to the Holy Savior, because the castle was captured on his feast day, while the second, the Sultan’s mosque, became another Catholic church dedicated once more to Saint Mavra. Both churches were allowed to conduct religious ceremonies of both Christian doctrines to achieve harmonious coexistence between Catholics and Orthodox, as desired by the Venetian administration of the castle.
The Venetians also decided to relocate the settlement of the castle to Amaksiki in 1685. They demolished all the dwellings within and outside the walls and constructed buildings intended for the Venetian administrative and religious authorities, as well as the military. These buildings included the House of the Proveditor, the Franciscan monastery, barracks, and a powder magazine.
In 1715, the Venetians withdrew their troops from the castle to send reinforcements to the fortress of Corfu, which was about to be attacked by the Ottoman fleet. On the day of their departure, Proveditor General at Sea, Daniele Dolfin, took all the cannons and ammunition with him and strategically detonated the walls of Agia Mavra at critical points to render it defenseless. As soon as the Ottomans learned of the castle’s evacuation, they dispatched a cavalry unit and occupied it without resistance.
On October 18, 1716, led by Proveditor General at Sea, Pisani, the Venetian fleet reached the waters just off the castle’s coastal walls. Witnessing this, the 20 Ottoman guards were overcome by panic and flee towards Aetolia. The Venetians once again seize control of Agia Mavra castle and proceed with necessary repairs.
In 1718, the Most Serene Republic of Venice assigned the task to the German Count John Matthias von der Schulenburg to fortify the castle, primarily focusing on the defense of the eastern and western fronts, which were most vulnerable to enemy attacks.
Therefore, earthworks were added to strengthen the walls in the most exposed areas, and vaulted chambers were embedded within their thickness, equipped with cannons to serve as artillery positions. The northern and northwestern walls appear to have received fewer reinforcements, as no sieges are documented on that side.
Following the models and innovative solutions of the European fortifications of the era, the bastion system (fronte bastionato) of the Lefkada fortress takes shape. The triangular bastions and the moats that encircled the castle, as part of the more advanced defensive system, now constituted the first line of defense, creating a protective shell around the castle. Moreover, the defensive system of the two gates was modified to align with Venetian standards.
Another notable addition during this period is the construction of the trapezoidal bastion at the conjunction of the mezzaluna with the eastern front of the castle. A similar shape had been adopted a little earlier for the bastion in the southeast, following the reconstruction of its original circular design. In 1719, Schulenburg erected a longitudinal barrack building within the bastion of Saint Francis, adjacent to the wall.
During the period from 1725 to 1797, the castle reached its largest extent, with only minor changes to its overall outline. The most significant alteration was the removal of the original inner core, gradually resulting in the demolition and “disappearance” of the acropolis.
