Already connected to inland Fujian by roads and canals, Quanzhou grew to international importance in the first century of the Song. It received an office of the maritime trade bureau in 1079 or 1087 and functioned as the starting point of the Maritime Silk Road into the Yuan, eclipsing both the overland trade routes and Guangzhou. A 1095 inscription records two convoys, each of twenty ships, arriving from the Southern Seas each year. Quanzhou's maritime trade developed the area's ceramics, sugar, alcohol, and salt industries. Ninety per cent of Fujian's ceramic production at the time was jade-colored celadon, produced for export. Frankincense was such a coveted import that promotions for the trade superintendents at Guangzhou and Quanzhou were tied to the amount they were able to bring in during their terms in office. During this period it was one of the world's largest and most cosmopolitan seaports. By 1120, its prefecture claimed a population of around 500,000. Its Luoyang Bridge was formerly the most celebrated bridge in China and the 12th century Anping Bridge is also well known.