Looking at the Saline Co highway map, Petra used to be northwest of Slater -- nr Rds NN & C. Afraid I don't know the history of it right now, other than a greatuncle was born there in 1874. The Marshall library people might be able to help you -- phone # Ihave is 660-886-3391. >Anybody know where the ghost town of Petra was located >in Saline county? Maybe near Slater? > >I understand the post office operated from 1842-1878. > > >Mike Flannigan > > > > > > >