On the 7th October 1571 the Holy League fleet captained by John of Austria defeated Suleyman the Magnificent's fleet in the Gulf of Lepanto, near the coast of Greece. This battle was decissive, because it stopped the Turk threat in the Eastern Mediterranean,

John of Austria, Philip II's half brother
Here ou have a map of the location of Lepanto, now called Naufpaktos:

And on this link you can download a presentation with an animated map of the battle:

