The Rites of Spring festival or RoSfest is a US annual progressive rock festival - established in 2004 - which takes place on the end of April or early in May. The festival was held at the Colonial Theatre in Phoenixville, Pennsylvania until 2007, and then moved to the Keswick Theatre in Glenside, Pennsylvania as of 2008. The festival moved to the Majestic Theater in historic Gettysburg, Pennsylvania for 2010 and 2011.
RoSfest was started in 2004 by George Roldan and Tom Smith. The intent of the promoters was to establish a new international progressive rock festival in the United States. The inaugural 3-day festival was held April 24, 25 & 26, 2004 at the famous Colonial Theatre located in Phoenixville, Pennsylvania.