Moles spend a large part of their lives in a self-dug burrow system below the ground. The animals push the loose earth that is a result of digging to the earth’s surface after every 50-100 cm. The result is a typical molehill, about 20 cm high. Sometimes we also come across huge hills with air holes all around. Below these molehills the moles make a nest in which they give birth to their young ones.