Country artists including Kacey Musgraves and Maren Morris are schedule to play the Spotify House at SXSW 2016 on Wednesday (March 16), but the crowd at the popup venue on Sunday night (March 13) got a huge surprise: a full set by none other than Willie Nelson.

Fans in attendance at the unexpected show in Austin, Texas, captured plenty of footage. Press play on the Instagram videos above and below to watch snippets of Nelson's set, which included "Always on My Mind," "On the Road Again," "Whiskey River" and more.

Nelson, who resides in Austin, has an event of his own scheduled during SXSW 2016. The country icon's Luck, Texas, ranch will be home to the 2016 Luck Reunion on Friday (March 18). The affair will feature two stages and more than 20 acts, including Jenny Lewis, Lucius, Blitzen Trapper, Billy Joe ShaverJohn Moreland, Nelson’s son Micah’s band Insects vs. Robots, Jack Ingram, Sam Outlaw, Jamie Lin Wilson, Daniel Romano, Ray Wylie Hubbard, the Black Lillies and many more are slated to perform. The lineup ranges from country to rock, folk to soul, all with influences in the “outlaw” sub-genre. More information about the 2016 Luck Reunion can be found on the event’s official website.

Loretta LynnWhitney RoseBobby Bare Jr. and more country, folk, Americana, bluegrass and alt-country acts are scheduled to play during SXSW 2016. The music portion of the annual event officially kicks off on Tuesday (March 15) and runs through Sunday (March 20).

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