GALLERY: Crossroads Guitar Festival 2013 Rebecca DirksApril 13, 2013Highlights from Friday and Saturday night at Crossroads. Photos by Kevin Mazur/WireImage"Urban joined John Mayer for a cover of the Beatles' ""Don't Let Me Down."" " Also click here to read our 20 Best Moments of Crossroads 2013 with fan videos.b-b-kingjohn-mayerwhats-newkeith-urbanperformance-galleriesartistsonline-onlyeric-claptonbluesArtistsBluesLessons