During their set at Primavera Sound, The National invited Bon Iver’s Justin Vernon out for a performance of “Slow Show” before The Walkmen’s Paul Maroon and Hamilton Leithauser closed the show with the band for “Mr. November” and “Terrible Love.”

Vernon, who was at the festival with Volcano Choir, also sat in with the band in 2013 for a pair of tunes at an Austin City Limits aftershow. The Bon Iver mastermind joined The National for “Terrible Love” and “Vanderlyle Crybaby Geeks.” Vernon played on the latter of the two in 2011 during The National’s slot on Toronto’s CBC Radio appearance.

The Vernon/National roots don’t stop there, as National guitarist Aaron Dessner collaborated with Vernon on “Big Red Machine” for the compilation release benefiting the Red Hot Organization (which raises money for HIV and AIDS research), Dark Was the Night.