The high surface area, large aspect ratio, and porous nature of nanorod arrays make them excellent to materials for many devices. Of the many synthesis techniques for forming nanorods, glancing angle deposition (GLAD) offers one of the more straightforward and flexible methods for ensuring control of alignment, porosity, and architecture of the nanorods. Here we demonstrate the first use of a dual-beam (focused ion beam (FIB) combined with scanning electron microscopy (SEM)) instrument to section and image the internal morphology of a nanorod array fabricated using the GLAD technique. We have used the FIB-SEM to reconstruct the 3D composition of TiO2 nanorods, allowing its to visualize for the first time the core structure's of many potential devices. We have also been able to probe the relationship between critical parameters such as diameter internanorod spacing 05), center-to-center spacing and nanorod population density ((w) over bar (act),,) and the depth of the nanocolumn (1) for a single homogeneous structure. A continuous data set was obtained from a single 5-mu m-thick GLAD film, avoiding the artifacts arising from the analysis of the top surfaces of multiple samples of varying thicknesses. An analysis of the acquired sectioned data has at its to determine that the critical nanocolumn parameters follow a power-law scaling trend with (w) over bar (act) = 9.41(0.35)nm (v) over bar (act) = 15.2(0.25) nm, (c) over bar (act) = 24.8t(0.31) nm, and d(act) = 3402t(-0.65) columns mu m(-2). Using the ElB/SEM images acquired for the TiO2 nanorods. we have also investigated the evolution of individual nanocolumns and have observed that bifurcation and branching play a significant role in the extinction or survival of these nanorods. These findings will allow for the optimization of nanorod properties for device applications. Also, the FIB sectioning and reconstruction process developed here will permit for the investigation of nanorod arrays formed from a range of synthesis techniques and materials.