London's Field Day Festival is known for its alternative style and pioneering bands. It's bill is usually very progressive and it has been sold out since it's first year opening in 2007.
Here is the 2013 Line up that is so far announced:
Animal Collective, Bat For Lashes, Amateur Best, Bobby Tank, Charanjit Singh, Charlie Boyer & The Voyeurs, Chvrches, Connan Mockasin, Daniel Avery, Daphni, Dark Bells, Dark Dark Dark, Daughter, Disclosure, Django Django, Do Make Say Think, Duologue, East India Youth, Egyptian Hip Hop, Everything Everything, Four Tet, Francois & The Atlas Mountains, F**ked Up, Gabriel Bruce, Ginger Baker Jazz Confusion, Guards, Happa, Hessle Audio DJs:, Ben UFO, Pangaea, Pearson Sound, How To Dress Well, J. Marinetti, Jacques Greene, Jagwar Ma, James Yorkston, John Cooper Clarke, Julio Bashmore, Karenn, King Krule, Koreless, Kurt Vile and the Violators, Kwes, Lee Gamble, Metz, Mount Kimbie, Mt Warning, Mulatu Astatke, Objekt, Palma Violets, Rainy Milo, Rudi Zygadlo, Savages, Seth Troxler, Shed, Solange, Splashh, Stealing Sheep, Stubborn Heart,
Thomas Mapfumo, Throwing Snow, Tim Burgess, TNGHT, Toy, Virals, Vondelpark, Wild Nothing