geographic area on a less-frequent basis (e.g., monthly). These often feature callers from other areas. Some general square dance conventions and festivals at the regional or state level include a Challenge hall, but they typically have very limited offerings above C1. National and international events The largest Challenge event currently operating is the multi-level Academy for Advanced and Challenge Enthusiasts (AACE), held annually in June. This event has dedicated halls for C1, C2, C3A, C3B, and C4. (It also includes an A2 hall.) Challenge dancing is included in the much larger National Square Dance Convention (NSDC), but there is typically only one hall for Challenge and the emphasis is on the lower Challenge levels. The annual convention of the International Association of Gay Square Dance Clubs (IAGSDC) has a much more extensive Challenge program that is attended by many non-gay dancers. In Europe, the biennial iPAC (International Plus, Advanced, and Challenge) convention offers dedicated halls for all the Challenge levels. Many other events held annually at various dance facilities attract Challenge dancers from a wide area who are interested in particular levels or callers. See also Square dance club Square dance program External links "Introduction to (Challenge) Square Dancing" by Lynette Bellini and Kathy Godfrey, January 2, 1996, retrieved October 27, 2005. "Challenge Square Dancing: Myths and Responses" by Clark Baker, January 2005, retrieved October 27, 2005. "Stan Winchester Singing Call Page" by Clark Baker, October 2006, retrieved November 6, 2006. CALLERLAB program lists CALLERLAB Challenge Dance Program Documents "Ceder Chest definitions" Detailed explanation of challenge calls, written by Vic Ceder Square dance