Hong Kong and Macau locates at the east and the west of the Pearl River Delta respectively, with a close distance of about 64 kilometres in between. Hong Kong and Macau bilateral relations could be traced back to the Middle Neolithic. Both Hong Kong and Macau were under the influence of the same type of Neolithic culture. Tools and ornaments used by both places show tight relationship in idea and trade between the two. Hong Kong became the first European colony in East Asia for being occupied by the Portuguese Empire as Tamão in the early 16th Century. Hong Kong and Macau competed and cooperated for being the commercial centres in the Pearl River Estuary. Eventually Hong Kong developed as one of the busiest entrepots and financial centres while Macau became a world gambling capital.