An area of raised bog on the northern slopes of the Pentland Hills, the Red Moss of Balerno to the north of Threipmuir Reservoir, 1¼ miles (2 km) south of the settlement of Balerno. Red Moss is the only raised bog in the City of Edinburgh. It represents a deep layer of peat which has accumulated over thousands of years and displays the characteristic dome shaped profile. In summer and autumn, the peatland is covered in a blanket of pink-purple heather, sundews, Ragged Robin and Sphagnum mosses. It provides a habitat for dragonflies, damselflies, frogs, toads and newts. It now serves as a Scottish Wildlife Trust reserve and, together with Bavelaw Marsh, the Moss forms the Balerno Common Site of Special Scientific Interest (SSSI), which was designated in 1971 and extends to 62.7 ha / 154.9 acres.