Paul McCartney will marry fiancée Heather Mills on June 11, 2002, at Castle Leslie in the village of Glaslough, Ireland.
The couple arrived by helicopter at the 17th-century estate on Sunday.
Around 300 guests are reported to attend, including Elton John, Eric Clapton, Lulu and the only other surviving member of the Beatles, Ringo Starr.
The wedding was between the rocker and the former model who sustained a disability in the 1990s was supposed to be hush-hush until estate owner Sir John Leslie let slip to reporters.
The couple have been engaged since last July. The marriage will be the first for Mills, 34, and the second for McCartney, 59. His first marriage, to photographer-turned-Wings keyboardist Linda McCartney (née Eastman) lasted 29 years, until her death from breast cancer in 1998.
Villagers nearby said they spotted Elton with singer Sir Cliff Richard in a car near Monaghan town, indicating Elton may have arrived early for the shows. EJW.com thinks that is hearsay as Elton performs tonight at the Ahoy Arena, Rotterdam, Netherlands!