The Cornerstone Society will host Charleston, S.C., mayor Joseph Riley to speak at the 2013 Cornelius O'Brien lecture.

Riley's topic will be "Preserving the Heart of a City: Charleston, S.C., in the 21st Century." Riley has served at mayor of Charleston for 38 years spanning 10 terms. He was presented with the National Medal of the Arts in 2009 and has received several other awards.

The lecture will be held at 1 p.m. May 9 at the Brown Gym. The lecture is a part of Preservation Month. Prior to the speech, there will be a picnic lunch that begins at noon. The picnic costs $10 per person and the lecture is free.

Tickets are available at the Lanier Mansion Visitor's Center at 601 W. First St. until May 2. For more information, call (812) 599-3447 or e-mail