Battle of Jaffa: Richard I Lionheart lands at Jaffa, now nearly captured by Saladin, and drives off the Muslim army. Richard has been withdrawing his forces because he cannot take and hold Jerusalem; Saladin attacked Jaffa because it as been serving as Richard's base of operations.
The Christian defenders of Jaffa fought hard, but they were too outnumbered: after three days Saladin's forces were able to storm the walls and capture everything but the citadel. Messengers reached Richard, who gathered what soldiers he could and sailed south.
When Richard arrives at Jaffa and learns how close the city is to being lost completely, he leaps into the waters and wades ashore at the front of his small force: 54 knights, a few hundred infantry, and 2,000 crossbowmen.
The Muslims in the city should be able to defend against this attack, but they are surprised at the ferocity of it and fear that it's only the start of a much larger relief force. This causes the Muslim soldiers to flee in a disorderly fashion, allowing their prisoners to take up arms and begin fighting again.
Saladin will eventually be able to reorganize his troops and mount a counterattack in three days, but the losses then will be even heavier than they are today. Saladin will have to give up and retreat entirely, leaving Jaffa in the hands of the Christian Crusaders.
This is the last major engagement of the Third Crusade. Soon, Saladin and Richard will negotiate a truce that leads to the Treaty of Jaffa. The Christians don't achieve their goal of capturing Jerusalem, but Christian pilgrims are granted the right to enter Jerusalem as well as protection while in the region.