Historically, the Ramadan cannon has served as a means to announce the end of the fast at sunset. However, today it plays an important but different role, namely to keep Ramadan traditions alive.
The firing of the cannon is believed to date from the early days of Islam, when the Fatimid caliph instructed that a cannon be placed at the highest point of a city so that during Ram-adan, all Muslims would be able to hear the shot signalling the end of the fast at sunset.
Ismailimail 