Although the Republic remained officially neutral in the war of Lepanto, numbers of Ragusan merchants and adventurers took advantage of it to make their own fortunes, many of them obtaining contracts for transporting troops, or hiring out their ships and crews. During the early part of the war Ragusan shipping suffered some damage, being plundered now by the Turks and now by the Christians, in spite of the treaty of protection; and as it was even feared that the city itself might be in danger, it was decided to strengthen the fortifications. An addition had been made to them in 1550-1558, when the large Forte San Giovanni was built; while the port was enlarged and improved with a new pier called the Diga delle Casse, constructed under the superintendence of Pasquale da Nola. In 1570 the Tower of Santa Margherita was begun by Sigismondo Hier;[471] and soon after Saporoso Matteucci, one of Piero Strozzi’s ablest pupils, was appointed commander of the garrison and director of fortifications. Santa Margherita was the last building erected from the foundations; subsequent additions were merely restorations, and the defences of the city have remained practically unaltered since that time.[472] The following year the battle of Lepanto was fought, in which the Turkish fleet was completely defeated. From this moment the decline of the Ottoman power may be said to begin. It is asserted that Ragusan galleys were found on both sides in this fight. Afterwards the city became the meeting-place for the Christian and Turkish commanders to arrange for the exchange of prisoners and the preliminaries of peace. Numbers of illustrious foreigners from all countries filled the town, and according to Appendini, sixty noble Christian captives were exchanged for an equal number of Turkish officers. But the Republic’s equivocal attitude during the war caused trouble with the Sandjakbeg of the Herzegovina, who in 1572 made various raids into the territory, laying waste some districts and carrying off many captives. Turkish pirates landed at Meleda and massacred all the monks, save those who took refuge in the caves.[473] At last, in 1573, a general peace was concluded, much to the disgust of the Venetians, who saw that in spite of the victory over the Turks it was not properly followed up, and the enemy was allowed to recuperate. Ragusa, however, was delighted, for the peace removed her dangers from both quarters. But even this spell of quiet was destined to be short-lived, and now began a series of calamities culminating in the great earthquake of 1667, which brought about the gradual decline of the Republic.