London's location is the United Kingdom.
The British Library is the national library of the United Kingdom and the second largest library in the world by number of items catalogued . Greater London . In 2012 , it had the highest GVA per capita in the United Kingdom at # 37,232 . London . Since at least the 19th century , `` London '' has also referred to the metropolis around this core , historically split between Middlesex , Essex , Surrey , Kent , and Hertfordshire , which today largely makes up Greater London , See also : Independent city § National capitals .