Springer International Publishing Switzerland 2015. The vortical flow structures in low and high Reynolds number lid-driven cavity flows are examined using Partially-averaged Navier-Stokes (PANS) and unsteady Reynolds-averaged Navier-Stokes (URANS) simulations. The spanwise aspect ratio (SAR) of the cavity is 3:1:1 and the Reynolds numbers based on cavity height and lid velocity are 104 and 106. It is demonstrated that, while the mean flow statistics are nearly the same for URANS and PANS, the complex vortex structures are captured much better by PANS. The difference between the URANS and PANS structures are even more distinct at higher Reynolds numbers. Furthermore, it is shown that the PANS small-scale statistics at different levels of resolution are self-similar and scale according to established turbulence theory.