Farmers once moved stock to the uplands for the summer months in a process called transhumance. This meant that home pastures could recover and be used for crops such as hay, while animals grazed on marginal land that would be unproductive at other times. The people who accompanied the stock lived in structures known as shielings. These were little better than camping huts or bothies built from stone, wood and earth and their remains may show up as low, usually rectangular, earthworks, sometimes clustered together in small groups. Each shieling will have an entrance, typically at one end.
Without excavation, shielings are almost impossible to date. Transhumance is an ancient practice and it probably only died out in the seventeenth and eighteenth centuries as increasing numbers of permanent upland farms were established.