In the Middle Ages there was a fishing lake called Kerlingarfjörðer at the mouth of the Múlakvísl. Probably it was not a fjord, but rather an extension of a river mouth. The name (isl. Kerling = the old woman) was created according to the land register book, after an old woman had fallen overboard from one of the settler ships and was carried away by the water. Around the year 1000 many farms seem to have found themselves on the Mýrdalssandur. Sources mention four parishes in Álftaver. These farms were, however, were mostly abandoned up to the 15th century, as a result of volcanic eruptions of the Katla, subsequent glacier runs and ashfall. At the beginning of the 21st century, some farms still exist in Álftaver.