Denver Turnverein Choir, Saturday, May 20, at the Denver Turnverein, 1570 Clarkson Street, sports a cultural heritage as rich as Denver itself. The outfit's namesake building dates back to the early part of the twentieth century and serves as the cultural center for Denver's German citizens and its Turners, a group whose founding predates the official statehood of Colorado. Today the men and women who make up the Turnverein choir continue to uphold the Turners' credo of peace through singing. Saturday's show will feature a songbook of German standards - everything from folk songs to beer-drinking anthems -- with a few American pop standards thrown in for fun. After the choir's performance, the hosts will fold up the chairs and clear the dance floor, where visitors of all ages will polka, waltz and jitterbug to multicultural tunes provided by Ronnie Eckhardt's Music Makers. A buffet of German-style food and a bar of Bavarian beer will add to the evening's retro-Rhineland excitement.