We resolve and address atoms in single sites of an optical lattice with a period of 5.3 µm created by a retroreflected, focused CO2 laser beam. In this one-dimensional lattice, the Lamb-Dicke limit can be fulfilled in all three spatial dimensions. Because of the negligible decoherence rate from spontaneous photon scattering such a lattice offers unique possibilities for the study of quantum phenomena in a controllable environment.