Each unit in the free-to-play game C-evo has a maximum "speed", the distance it can normally travel in one turn. The minimum for a ground unit is 1.5 (i.e., one diagonal step - N, S, E, or W on an isometric map - that's not using a road or river). Various additions can be made once you have researched Horseback Riding. Naval units start at 2.5 for the predesigned units (Longboats). Minimum is 3.5 for units you design. That can be increased by various factors as you do more research. Air units start at 8.5 but any designed after you know Rocketry are 12.5. You cannot enhance those.