Cardiff is situated near the Glamorgan Heritage Coast and has an official population of 317,500 people. The main industry is based on coal – making iron and steel. The town has annual festivals such as The Big Weekend Festival. Cardiff has many landmark buildings such as the Millennium Stadium, the Pierhead Building and the National Assembly for Wales. Cardiff is also famous for Cardiff Castle, St David's Hall, Llandaff Cathedral, the Wales Millennium Centre and Cathays Park. Cardiff Castle is a major tourist attraction in the city and is situated in the heart of the city centre. Other major tourist attractions are the Cardiff Bay and many other sites of interest including the Cardiff Bay Barrage and the famous Coal Exchange.