Liverpool would've been too obvious. The "Five Days of Peace, Love and Rock 'n' Roll" known as Abbey Road on the River promises five day's worth of over 50 Beatles-related bands, with an annual attendance around the 20,000 mark.
Anyone under 21 gets in free, which ironically, all of the Beatles members were when they formed the band. If you fancy stretching your vocal chords, the Beatles Song Singing Contest promises the winner prizes to the tune of $10,000.