450th Factoid U.S. Postage stamp commemorating St. Augustine’s 400th anniversary By admin - August 29, 2014 0 1133 Share on Facebook Tweet on Twitter Counting down to the 450th anniversary of St. Augustine Aug. 29, 1965 U.S. Postage stamp commemorating St. Augustine’s 400th anniversary was unveiled. It was announced that the stamp would be issued in St. Augustine.