The structure and dynamics of the {0001} (basal), {10(1) over bar0} (prism), {20(2) over bar1}, and {2(11) over bar0} ice Ih/water interfaces have been investigated using molecular dynamics and the flexible CF1 central force model of water. The translational order profile, the average density profile, and the diffusion profile have been calculated for all four interfaces as a function of distance normal to the interface. Dynamical molecular trajectories have been used to explore the loss of translational order from within the crystal region, through the interface, and into the liquid region. The thickness of the interfaces has been determined from each order parameter and compared with results from rigid models of water and experiment. The high index faces have thinner interfacial regions than the basal and prism interfaces. All interfacial regions contain molecules that are neither ice-like nor water-like. (C) 2001 American Institute of Physics.