A numerical investigation of lid driven deep cavity flows of incompressible fluid is presented, adopting a finite element method (FEM). The formation of counter–rotating primary vortex, secondary vortex, left corner and right corner vortices are analysed, at various widths to height aspect ratios of cavities and increasing inertia is considered. The impact of corresponding aspect ratios, taken from 1:1, 1:2, 1:3 and 1:4. The effects of the moderate inertial values from Re =100 to 3000 are examined. The influence of both aspects, ratios and inertia on the formation of vortices, intensity and magnitude of the recirculating region are observed. Various number of vortices and their location of centres, and many other flow features in the deep cavities are also investigated. The results are compared with other numerical studies.