An isthmus is a strip of land joining two other areas of land separated by water. This land is usually an area raised significantly above sea level, forming a stable land mass. The general interpretation of these formations is that the adjoining land has been submerged. This means that an isthmus is like a ridge, a raised area of land above sea level. Some isthmuses are large, forming continental land bridges. Isthmuses have affected human colonization of the world and history