The cosmopolitan, colourful city of Cairns in far north Queensland is a tourist-orientated centre because it is the gateway to two of the world's most awesome World Heritage Sites, the Great Barrier Reef and the 110-million year old Daintree rainforest. Cairns started life as a small fishing encampment, which received an injection of prosperity in the 19th century when gold was discovered to the north and tin and timber began to be exploited in the nearby Atherton Tablelands. The harbour and fishing operations increased in importance, and tourism arrived in the early 20th century when marlin fishing became popular, and the world discovered the delights of exploring the Great Barrier Reef. Aided by its pleasant, warm climate the relaxed tropical town has now become a frenzied international tourism centre, flooded with visitors most of the year, its streets lined with souvenir stores, eateries and some first class hotels. The harbour is clogged with streamlined pleasure boats, and the offshore islands bristle with resorts. To cater for tourists the city fathers have even created a man-made salt-water lagoon and sandy beach on the Esplanade to replace the original muddy swamp that crowned Trinity Bay. The international airport keeps the visitors coming in, as the city, with its festive air, expands to accommodate them.