[gostsamo]

Yep, bells were used to regulate communal activities like prer, holidays, weddings, burials, and danger. Later - announcing the hour. They are intrusive and expensive though, so for long-distance communication they had to use other means like fire, smoke, doves, and horse curriers.

[Cthulhu_]

Also flags, lamps (with shutters on ships, lighthouses), telegraphs (https://en.wikipedia.org/wiki/Telegraphy), and beacons so that Gondor can call for aid.