A bell tower is a structure designed to house one or more bells, typically found in churches, schools, or public buildings. These towers can vary in height and architectural style, often serving as a prominent feature in a community. The bells are usually rung to signal the time, mark special occasions, or call people to worship. Many bell towers are part of larger structures, such as cathedrals or town halls. They can be made from various materials, including stone, brick, or wood, and may include a clock mechanism. Some famous examples include the Campanile of St. Mark's Basilica in Venice and the Big Ben tower in London.