London is a popular centre for tourism, one of its prime industries, employing the equivalent of 350,000 full-time workers in 2003,[189] while annual expenditure by tourists is around £15 billion.[190] London attracts over 14 million international visitors per year, making it Europe's most visited city.[191] London attracts 27 million overnight-stay visitors every year.[192] In 2010 the ten most-visited attractions in London were:[193]