To mark the 50th anniversary of the massacre, U2 today shared on social media a new, acoustic performance by Bono and The Edge of “Sunday Bloody Sunday.”

Thirty years ago tonight, U2 braved a cold Colorado rainstorm to perform at the fabled Red Rocks Amphitheatre just west of Denver, a concert on the band’s War tour that was filmed and released on video as “Under a Blood Red Sky,” cementing Bono and Co.’s reputation as live act.