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What is Antennas to hell by Slipknot
Antennas to Hell is the first greatest hits compilation album by American heavy metal band Slipknot
How popular was the antennas to hell album by Slipknot?
Slipknot's Antenas to Hell album debuted at number 18 on the U.S. Billboard 200 with sales of more than 16,000 copies in its first week
When wasthe album Antennas to Hell by the band slipknot released?
Slipknot's Antennas to Hell album was released on July 23, 2012.
What was the band slipknots Knotfest?
slipknot's annual music festival

Question: When did that take place?
Self-contained rewrite: When did Slipknot's annual music festival Knotfest take place?