Mountain guns are artillery pieces designed for use in mountain warfare and areas where usual wheeled transport is not possible. They are similar to infantry support guns, and are generally capable of being broken down into smaller loads (for transport by horse, human, mule, tractor, and/or truck).
Due to their ability to be broken down into smaller "packages", they are sometimes called pack guns or pack howitzers. During the U.S. Civil War these small portable guns were widely used and were called "mountain howitzers."
The first designs of modern breechloading mountain guns with recoil control and able to be easily broken down and reassembled into highly efficient units were made by two Greek army engineers, P. Lykoudis and Panagiotis Danglis (after whom the Schneider-Danglis gun was named) in the 1890s.
Mountain guns are largely outdated, their role being filled by mortars, multiple rocket launchers, recoilless rifles and wire-guided missiles. Most modern artillery is manufactured from light-weight materials and can be transported fully assembled by helicopters.