In the closing stages of the siege (1645-1669), acting on intelligence from the Venetian-Cretan traitor Andreas Barozzi, the Turks concentrated all their efforts and firepower on the weakest Sampionara and St. Andrew Bastions at the eastern and western extremities of the fortifications, eventually forcing the Venetians to negotiate the surrender of the city.

Both of the above bastions were almost completely razed to the ground in the siege, but were later redesigned and rebuilt by the Turks.