Why and when do the bells of the tower of Pisa ring?

The bells of the Leaning Tower of Pisa ring primarily for ceremonial and religious purposes, such as marking the time and calling people to prayer. They also ring during special events and celebrations, including festivals and significant occasions in the city. The bells have been in use since their installation in the 14th century, although their ringing has been more regulated in modern times to preserve the structure and manage sound levels.