We study spatial coherence near a classical environment by loading a Bose-Einstein condensate into a magnetic lattice potential and observing coherent diffraction. Even very close to a surface (5μm), and even when the surface is at room temperature, spatial coherence persists for a relatively long time (≥500ms). In addition, the spatial coherence extends over several lattice sites, much farther than the atom-surface separation. This opens the door for atomic circuits, and may help elucidate the interplay between spatial dephasing, inter-atomic interactions, and external noise.