You can see horizontal lines at the side of the central hill in the image. These are sheep roads. Sheep like it easy and they find the easiest way to climb a hill. Over time, these small roads appear, where sheep regularly roam.
When hiking in an area where sheep roam freely, like in Iceland or Scotland, and you want to go up- or downhill, look out for these sheep roads and follow them. Sheep have found the easiest way to walk uphill or downhill because they are kind of lazy. So, they try to avoid unnecessary efforts. In this image all the roads are in horizontal directions, but you can also find them leading up and down.