Liberty Bell
Ever since the city began in 1682, Philadelphia had been using its city bell to make its people know about meetings or civil danger. The first bell hung from a tree behind the Pennsylvania State House, now known as Independence Hall. In 1751, a bell tower was built in the Pennsylvania State House, and the leaders there began looking for a bell which could be heard from far away (the city was growing larger quickly). Isaac Norris, speaker of the Pennsylvania Provincial Assembly, ordered the colony's London agent, Robert Charles, to get a "good Bell of about two thousands pound weight".