Sound travels fastest through a solid, when compared to a liquid or a gas. The molecules in a solid are denser and can be disturbed at a more rapid pace.
Sound travels in mechanical waves of energy through different media, such as solids, liquids or gases. Waves cause the molecules of a medium to collide as it passes through the medium. Because the molecules of a solid are closer together than those of a liquid or gas, the molecules of a solid collide at a faster rate. Altitude, humidity and temperature are additional factors that influence the speed that sound passes through a medium.