Liquid storage system

Disclosed is a liquid storage system comprising a tank (16) for containing a liquid, said tank (16) enclosing a liquid storage space (14), and a plurality of spaced apart protrusions (18b) extending from an internal surface of the tank (16) into the liquid storage space (14). The protrusions (18b) are resistant to deformation and deflection caused by shockwaves (30) within a liquid in the tank (16) resulting from impact of a projectile (24) with the tank (16), for example, the protrusions (18b) may be rigid and be polygonal prisms in shape.