Three-dimensional (3D) metal photonic crystals (MPCs) can exhibit interesting electromagnetic properties such as ultra-wide photonic or "plasmonic" band gaps, selectively tailored thermal emission, extrinsically modified absorption, and negative refractive index. Yet, optical-wavelength 3D MPCs remain relatively unexplored due to the challenges posed by their fabrication. This work explores the use of multi-photon direct laser writing (DLW) coupled with electroless metallization as a means for preparing MPCs. Multi-photon DLW was used to prepare polymeric photonic crystal (PC) templates having a targeted micron-scale structure and form. MPCs were then created by metallizing the polymeric PCs via wet-chemical electroless deposition. The electromagnetic properties of the polymeric PCs and the metallized structures were characterized using Fourier transform infrared spectroscopy. It is shown that metallization transforms the optical properties of the structures from those of conventional 3D dielectric PCs to those consistent with 3D MPCs that exhibit ultra-wide photonic band gaps. These data demonstrate that multi-photon DLW followed by electroless deposition provides a viable and highly flexible route to MPCs, opening a new path to metal photonic materials and devices.