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With loads in the mN-range and displacements in the nm-range, nanoindentation testing allows studying the local mechanical properties of individual grains. It may be expected that grain orientation affects Young's modulus and hardness. In this study, we characterize the influence of grain orientation on the nanoindentation behaviour of pure alpha-iron. Individual grains with < 001 >, < 101 >, and < 111 > surface normals are identified by electron back-scatter diffraction, and these grains are subsequently indented. Grain orientation clearly has an effect on the determined hardness; however, it has only a negligible effect on the direction-dependent Young's modulus. These results may be rationalized by considering the nature of the activated slip systems and the complex stress state below the indenter tip. The results demonstrate how anisotropic elastic and plastic properties affect nanoindentation measurements.