How Are Mountains Formed? Mountains are formed over long periods of time by forces of the earth. Mountains just don’t appear in any place. Most are formed when plates, or huge pieces of the Earth’s crust, pull and push against each other. Great mountain ranges are formed by the movement of tectonic plates. Convection currents deep in the mantle of the earth, begins to well up towards the surface. As the pressure increases, it sets the crustal plates in motion. There are different kinds of mountains - Volcanic, Folded, Fault-block, and Dome mountains. Volcanic mountains are formed when magma comes up t