The growing demand for cost-effective and scalable nanofabrication techniques has positioned porous anodic aluminum oxidePositioned porous anodic aluminum oxide (PAAO) as a powerful and versatile alternative to more complex and costly methods. In this chapter, we present a straightforward experimental approach for synthesizing PAAO periodic templates in two different configurations, nanodomesNanodomes (dielectric substrate) and nanoconcavitiesNanoconcavities (conductive substrate), with tunable pore diameters by employing acid mixtures as electrolytes at varying anodization voltages. These templates serve as multifunctional platforms for the fabrication of plasmonic metamaterials. We investigate by reflectance spectra in the UV–Vis-IR range, the optical response of nanostructured thin films, referred to as metafilms, deposited on PAAO using various conductive materials, including aluminum (Al), silver (Ag), lead (Pb), niobium (Nb), and bismuth (Bi). The results highlight the potential of PAAO-based nanoarchitectures in tailoring plasmonic behavior across a broad spectral range, paving the way for novel applications in sensing, photonics, metamaterials design, and even medical applications such as biocompatible plasmonic materials.