The Grateful Dead unite for 50th

Billboard exclusively reports that Phish guitarist Trey Anastasio will join the four living original members of The Grateful Dead for three 50th-anniversary shows July 3-5 at Soldier Field in Chicago.

The Dead's last performance with Jerry Garcia, who died in August 1995, was at the same 55,000-seat capacity venue on July 9, 1995.

The sense of closure is no ­accident: These shows are likely to be the finale for the "core four," as the ­surviving members are now known: Bob Weir, 67; Phil Lesh, 74; Mickey Hart, 71; and Bill Kreutzmann, 68.

"These will be the last shows with the four of us together," Weir tells Billboard.