The lake is described in Lewis's Topographical as being an irregular oval shape, possibly long by broad. A freshwater lake, most sources focus on the clarity of the water, with the term "gin clear" being used frequently to describe it. It sits approximately 97 metres (312 ft) above sea level and covers approximately 500 hectares. It plays a vital part in local life from being the water supply for Collinstown to playing an essential part in the social, historical and recreational life of the area.