 The city grew as an important centre for the wool trade in the 14th century, and later became a major coal mining area.The port developed in the 16th century and, along with the shipyards lower down the River Tyne, was amongst the world's largest shipbuilding and ship-repairing centres.Newcastle's economy includes corporate headquarters, learning, digital technology, retail, tourism and cultural centres, from which the city contributes £13 billion towards the United Kingdom's GVA.