The ice-water interface plays an important role in determining the outcome of both biological and environmental processes. Under ambient pressure, the most stable form of ice is hexagonal ice (I-h). Experimentally probing the surface free energy between each of the major faces of I-h ice and the liquid is both experimentally and theoretically challenging. The basis for the challenge is the near-equality of the surface free energy for the major faces along with the tendency of water to supercool. As a result, morphology from crystallization initiated below 0 degrees C is kinetically controlled. The reported work circumvents supercooling consequences by providing a polycrystalline seed, followed by isothermal, equilibrium growth. Natural selection among seeded faces results in a single crystal. A record of the growth front is preserved in the frozen boule. Crystal orientation at the front is revealed by examining the boule cross section with two techniques: (1) viewing between crossed polarizers to locate the optical axis and (2) etching to distinguish the primary-prism face from the secondary-prism face. Results suggest that the most stable ice-water interface at 0 degrees C is the secondary-prism face, followed by the primary-prism face. The basal face that imparts the characteristic hexagonal shape to snowflakes is a distant third. The results contrast with those from freezing the vapor where the basal and primary-prism faces have comparable free energy followed by the secondary-prism face.