  In two- and three-dimensional structures, topologically-protected chiral edge
modes offer a powerful mean to realize robust light transport. However, little
attention has been paid so far to robust one-way transport in one-dimensional
systems. Here it is shown that unidirectional transport, which is immune to
disorder and backscattering, can occur in certain one-dimensional metacrystals
with long-range hopping without resorting to topological protection. Such
metacrystals are described by an effective Hermitian Hamiltonian with broken
time reversal symmetry, and transport does not require adiabatic (Thouless)
pumping. A simple implementation in optics of such one-dimensional
metacrystals, based on transverse light dynamics in a self-imaging optical
cavity with phase gratings, is suggested
