  Magnetic charge propagation in bulk frustrated materials has yielded a
paradigm-shift in science, allowing the symmetry between electricity and
magnetism to be studied. Recent work is now suggesting magnetic charge dynamics
upon the spin-ice surface may have important implications in determining the
ordering and associated phase space. Here we detail a 3D artificial spin-ice, a
3D nanostructured array of magnetic islands which captures the exact geometry
of bulk systems, allowing field-driven dynamics of magnetic charge to be
directly visualized upon the surface. Using magnetic microscopy, we observe
vastly different magnetic charge dynamics along two principle directions. These
striking differences are found to be due to the surface-termination and
associated coordination which yields different energetics and interaction
strengths for magnetic charges upon the surface.
