in Bangor, Bay Chambers Summer Music Festival in Rockport, Bowdoin International Music Festival, Kneisel Hall Chamber Music Festival, Portland Chamber Music Festival, Salt Bay Chamberfest in Damariscotta, Sebago – Long Lake Music Festival in Harrison, Saltwater Celtic Music Festival, Ossipee Valley Music Festival in South Hiram, East Benton Fiddlers Festival and Contest, Sweet Chariot Music Festival on Swan's Island, Saddleback Mountain Bluegrass Festival, Frantasia at the University of Maine at Farmington, Treat Memorial Library in Livermore Falls, American Folk Festival in Bangor, Thomas Point Beach Bluegrass Festival in Brunswick, the Gamper Festival of Contemporary Music in Bowdin and the Sebago – Long Lake Festival Players. Maine is home to several prominent professional organizations, including the Portland Symphony Orchestra, the Bangor Symphony Orchestra, the Maine Country Music Association Hall of Fame, the Down East Country Musical Association and the Maine Academy of Country Music. The Maine State Music Theater in Brunswick has operated since 1959 and is one of three professional music theaters in the state; the others are Northport Music Theater in Northport, which opened in 2007, and Ogunquit Playhouse in Ogunguit, which opened in 1933. Portland is also home to the Portland Choral Arts Society and the Portland String Quartet. The DaPonte String Quartet is the only other professional string quartet in Maine. The Portland Opera Repertory Theatre and Opera Maine are the main outlets for opera in the state. Outside of Portland, there are pockets of people who preserve the traditional musical styles of their ancestors, including the Swedish music of Stockholm and New Sweden, the French-Maine community (especially in Upper St. John Valley, home to the Acadian Festival) and the ethnic Russian music of the Kennebec River community in Richmond. Maine's musical heritage also include the longstanding men's a cappella group, the Meddiebempsters, at Bowdoin College, and Bates College's all-male Manic Optimists. Original compositions about Maine and by Maine composers are stored in the Maine Collection at the Bagaduce Music Lending Library in Blue Hill. With over 225,000 separate titles, this library houses the largest publicly available sheet-music collection in North America. Folk, country, and bluegrass music Maine has a long folk fiddling tradition, including Mellie Dunham, which has helped inspire many modern bluegrass musicians. Maine's bluegrass and fiddling tradition is celebrated at the Eastern Maine Music Festival. There is also a Bluegrass Music Association of Maine. Maine's contributions to bluegrass include Clarence and Roland White of