Dublin is the capital city of Ireland located on its east coast. It has over 1.5 million residents and was originally called 'Dubh Linn' meaning 'Black Pool' referring to an ancient natural lake. O'Connell Street is Dublin's main road and the widest urban street in Europe. St. Patrick's Day is celebrated worldwide on March 17th and has become a long weekend festival in Dublin. Trinity College in Dublin was established by Queen Elizabeth I and is home to the historic Book of Kells manuscript. Phoenix Park is the largest city park in Europe and home to Dublin Zoo, the presidential residence, and herds of fallow deer.