What area serves as the barter center for Fort Repose after The Day in the novel, Alas, Babylon?

Marines Park is the barter center for Fort Repose after The Day. The raised octagonal bandstand is an open-air market and gathering spot for traders with goods to swap. The columns that support the roof are used to tack want-ads or offers to trade. The well-kept turf around it becomes overgrown and covered with weeds and sandspurs. Two drinking fountains are marked one for whites only and the other coloreds only but neither works.