Windmill Farm Nature Reserve is a 200 acre site on The Lizard comprises grassland and heath land with some scrub, bog, swamp, and hedgerow. The construction of two ponds and a scrape have provided habitat, together with arable crops for birds. The adult marsh fritillary may be seen on the wing from mid-April to July. The reserve contains a 17th-century windmill, Bronze Age barrows, and Second World War pillboxes. The site that is jointly owned by Cornwall Wildlife Trust (CWT) and Cornwall Bird watching and Preservation Society (CBWPS). The reserve is of interest to naturalists but also has a rich archaeological heritage ranging from Bronze Age Remains, Mediaeval field boundaries, 18th Century tenements and crofts, WW2 pillboxes and the famous Lizard landmark - the Windmill itself. The reserve is managed and run by the CWT, CBWPS and a small group of local volunteers.