Castle Hill National Nature Reserve
Forty-seven hectares of unimproved chalk grassland on the Downs between Lewes and Brighton, thick with wildflowers in summer
Castle Hill has turf that’s never been ploughed or fed with fertiliser, a rare survival on this stretch of the South Downs. Orchids, wild thyme and horseshoe vetch grow here, along with whatever butterflies find them worth feeding on. The reserve sits right on the escarpment edge, with the ground dropping away sharply to the Weald on the far side of the ridge.
One of the easiest ways to spot old, undisturbed grassland like this is to look down rather than out. Yellow meadow ants build their mounds very slowly, so big, well-established anthills on a hillside are a reliable sign of ground that hasn’t been disturbed for decades, sometimes centuries. Castle Hill has plenty of them.
The reserve joins up with Kingston Escarpment & Iford Hill and Bullock Hill along the same stretch of downland, and the Downs here saw rather more dramatic history in 1264, when the Battle of Lewes was fought a few kilometres to the northeast. Falmer station is the nearest stop if you’re arriving by train; otherwise it’s open access land, walkable any day of the year.
