A raised beach is an elevated beach that is above sea level because of an uplift of the land or a retreat of the sea. A raised beach is often bounded on its inland edge by old cliffs, sometimes with caves. The uplift of land may have been the result of tectonic movements or the result of isostatic re-adjustment of the land after ice has melted. When the weight of ice has been removed by melting, the land gradually rises, relative to the sea. The same effect can be produced by the retreat of the sea, and this occurred when snow and ice increased during the glacial phases; as water becomes locked in ice and snow there is less water in the sea and it retreats from the beach.