One of Europe's most dynamic and popular pride celebrations, London Gay Pride officially takes place in late June - the dates this year are June 25 to June 30, 2013. It's one of the most well-attended such events in the world, drawing more than 500,000 participants. Last year was an especially huge gathering, because London Pride coincided with WorldPride (which will take place in conjunction with Toronto Gay Pride in 2014) and EuroPride (which will next take place in Marseilles in July 2013).
Numerous gay clubs, hotels, pubs, and restaurants will also be holding events and offering special promotions during London's Gay Pride. Check out About.com London's excellent primer on the London Pride Celebration, as well as such useful gay London resources as London Gay Guide Online and the Patroc London Gay Guide. Also take a look at the excellent GLBT site produced by the city's official tourism organization, the London Tourist Board.