Hear one of St. Petersburg's great cultural treasures, the Austin Pipe Organ, in a major musical performance by virtuoso organist Dr. Marilyn Keiser. Dr. Keiser has been described as "one of the world's most brilliant and sought-after concert organists and teachers." The concert is in celebration of the organ's 50th anniversary of its installation at the Cathedral Church of St. Peter (140 Fourth Street N, St. Pete). The performance begins at 5 p.m. There is a $10 suggested donation for attendees.