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In the vascular niche, the extracellular matrix (ECM) provides a structural scaffold with a rich ligand landscape of essential matrix proteins that supports the organization and stabilization of endothelial cells (ECs) into functional blood vessels. Many of the physical interactions between ECs and macromolecular components of the ECM occur at both the micron and sub-micron scale. In addition, the elasticity of the ECM has been shown to be a critical factor in the progress of the angiogenic cascade. Here we sought to determine the effect of substrate topography and elasticity (stiffness) on EC behavior. Utilizing a unique SiO2 substrate with an array of micropillars, we first demonstrate that micropillars with heights >3 μm significantly decrease EC adhesion and spreading. Fibronectin (Fn) patterning onf 1 μm high micropillars enabled EC adhesion onto the micropillars and promoted alignment in a single-cell chain manner. We then developed a robust method to generate a soft micropillar substrate array made of polydimethylsiloxane (PDMS), similar to the SiO2 substrate. Finally, we examined the kinetics of EC adhesion and spreading on the soft PDMS substrates compared to the stiff SiO2 substrates. Cell culturing on the PDMS substrates demonstrated an enhanced EC elongation and alignment when compared to stiff SiO2 with similar topographical features. We conclude that the elongation and alignment of ECs is co-regulated by substrate topography and stiffness and can be harnessed to guide vascular organization.