  Wave propagation control is of fundamental interest in many areas of Physics.
It can be achieved with wavelength-scaled photonic crystals, hence avoiding low
frequency applications. By contrast, metamaterials are structured on a
deep-subwavelength scale, and therefore usually described through
homogenization, neglecting the unit-cell structuration. Here, we show with
microwaves that, by considering their inherent crystallinity, we can induce
wave propagation carrying angular momenta within a subwavelength-scaled
collection of wires. Then, inspired by the Quantum Valley-Hall Effect in
condensed matter physics, we exploit this bulk circular polarization to create
modes propagating along particular interfaces. The latter also carry an edge
angular momentum whose conservation during the propagation allows wave routing
by design in specific directions. This experimental study not only evidences
that crystalline metamaterials are a straightforward tabletop platform to
emulate exciting solid-state physics phenomena at the macroscopic scale, but it
also opens the door to crystalline polarized subwavelength waveguides.
