 This is because the landslides have put a several-metres-thick layer of earth on top of the cave essentially putting it farther into the ground than it originally was.The layer of earth contributes to a better preservation of the cave as a form of insulation that makes the temperature inside it more even and the cave less likely to be subject to frost and water damages.Cow-farming was discontinued at Hellar farm in 1982 and since then Hellnahellir has not been used to store hay in it.