Template-assisted metallic nanowires, or hollow nanotubes, were synthesized by controlled electrodeposition of a metal salt under a controlled ac frequency in an anodic alumina membrane (AAM). Homogeneous large dimension AAM (D=5cm) was prepared by a modified two step anodization, using a specially designed reaction vessel that holds the sample perpendicular during the anodization. A ripping process, i.e. applying an opposite current after the anodization, easily separated the AAM from the Al substrate. TEM, SEM, and AFM were used to investigate the AAM structure, pore density and size, and distribution. Large aspect ratio metallic nanoparticles were prepared in an AAM within hexagonally close packed (hcp) alumina nanochannels.