A modular wall block is adapted for being assembled together with a number of other blocks in stacked courses to form a retaining wall. The wall block has a front and rear, top and bottom, and opposing sides. The top and bottom define respective substantially planar stacking surfaces. A shear lug projects from one of the planar stacking surfaces of the top and bottom. A block-locating jut is formed with at least one of the opposing sides, and projects from the side at a point intermediate the top and bottom towards one of the planar stacking surfaces. The block-locating jut defines a base surface substantially coplaner with the stacking surface, and a lug-engaging shoulder adapted for engaging a shear lug of a wall block located in an adjacent stacked course.