What: Gravel, sand and stones that have been deposited by waves and currents
How: Waves and currents wash away sand, gravel and stones from the shores, which then end up to less exposed areas on the seabed. The land uplift has then raised the deposits out of the sea. Sometimes you can find beach ridges in these deposits. They are about a metre-high ridges on the terrain, and nowadays they are often covered with trees and other vegetation.
Where to see: Many places at the Mjällom peninsula, for example the area west of the golf course at Norrfällsviken.
Fun fact: Beach ridges show you the development of the shoreline. If you know their height above sea level, you can calculate when a particular beach ridge was at sea front.