According to the invention, a side sill of a vehicle body of a motor vehicle comprises an outer shell and an inner shell connected to each other via flanges. A reinforcement is removably attached to the outside of the outer shell, which reinforcement extends essentially over the entire length of the side sill in the vehicle longitudinal direction. By means of this reinforcement, a load introduced onto a point of the side sill is absorbed and distributed. This is especially relevant to achieving better crash characteristics in a side pole crash.