Old Winchester Hill

Site feature providing a more detailed description, photos and other information for the butterfly observer.

Photo 1 - Steep Downland Slope North-East Of The Hill Fort 


  • National Nature Reserve on chalk downland owned and managed by English Nature.

  • Site crowned by Iron Age hill fort providing fine views.

  • Chalkhill Blue can be very numerous across the site.

  • Other species include Dark Green Fritillary, Adonis Blue, Silver-spotted Skipper, Grizzled Skipper, Dingy Skipper and Clouded Yellow.

  • The possibility also to see  Duke of Burgundy, although numbers very small.


Old Winchester Hill is a National Nature Reserve on the South Downs just east of the village of Warnford in the Meon valley. It is also the site of an Iron Age hill fort with many prehistoric features still visible, such as earthworks, barrows and tumuli. The flat-topped summit of the fort itself, complete with triangulation pillar provides fine views. This large nature reserve is noted especially for its flora, which includes at least 6 species of orchid, and of course for its butterflies.


The hill can be prolific for Chalkhill Blue, and there is also a reasonable population of Dark Green Fritillary, as well as common downland species. Silver-spotted Skipper used to do quite well here, but numbers have declined in recent years, probably due to the reduction in short sward areas which they need. A number of attempts have been made by English Nature since the early 2000's to re-introduce Adonis Blue to Old Winchester Hill, and after a few up and down years, the species seems to have a reasonably secure foothold, despite its modest population. For this feature, it is convenient to use two widely separated locations which are both good for butterflies, since other areas of the reserve can be readily accessed from one or other of them. I will assume access is from the main car park (map), however for the fort area, there is also limited road parking close to pedestrian entrances further south along the minor road. 


The first location is at the bottom of the car park slope. Hence, from the car park, enter the reserve through the gate and turn almost immediately right, passing in front of a gazebo shaped structure containing visitor information (take a look!). Continue through another gate and head straight down the grassy slope. Depending on the time of year, species which can be found on this heavy rabbit grazed area include Chalkhill Blue, Meadow Brown and Small Heath. Towards the bottom of the slope, just before the path takes a left turn, pause and look around. The area of more varied vegetation to your left (map) and in front of you, is a good location to look for several species, depending on timing. In this area, there are Common Blue and I have seen (in small numbers) Grizzled Skipper, Dingy Skipper and even Green Hairstreak. Chalkhill Blue can be present in significant numbers and it is also an area where Adonis Blue and Clouded Yellow can sometimes be seen. In August you may be lucky to find a few Silver-spotted Skippers either on the grassy path down the slope or in the shorter sward area, but the species seems now to be somewhat scarce here.


If you continue along the path as it turns, you reach an area of steep open downland (Photo 1 at top of page). Look here for fast-flying Dark Green Fritillaries during July. However, this very active species rarely seems to settle for long on this site and can be difficult to photograph. The verdant lower slopes of this downland, before it meets woodland, are one of the locations on this large reserve where a few Duke of Burgundy have been recorded in recent years (during May). However, departing from the paths is discouraged, bearing in mind the site was used in World War II for mortar testing. Hence, staying on the path, you enter this woodland and emerge a few minutes later into another area of downland. It is uphill from here, keeping to the paths, to the fort area which is close to the second location I have selected for this site feature. However, I will describe the route to the fort as if making a separate visit, starting from the car park.

Photo 2 - View Into The South Field From The Fort


In this case, after entering the reserve from the car park, just continue along the main path. The fort is just over 1km from the car park, the path heading south parallel to the road for about half that distance, before turning right towards the fort. In the first section, Marbled White can be numerous amongst the long grasses, as well as Small/Essex Skippers, Meadow Brown and Chalkhill Blue. It is notable that the latter species can be found in almost all grassland areas of the reserve at the peak of their season. Some areas of the fort area itself (such as the ramparts) may be roped off to protect nesting birds, but butterflies are normally plentiful even along the rampart edges (Chalkhill Blue, Small Heath, Small/Essex Skipper, Meadow Brown, Painted Lady and even the occasional Clouded Yellow) and a full circuit around the fort is worthwhile if time permits.


The second specific area to explore is the south field which is accessed via an open gate on the south side of the fort (shown in Photo 2 above). The lower part of the slope and the scrub area towards the bottom, are usually the best places for butterflies with a good variety of common species. Chalkhill Blues can be numerous here and there are small populations of Brown Argus, Adonis Blue and Silver-spotted Skipper, the latter as usual, favouring the short sward areas.

© Copyright Alan Thornbury's Hampshire Butterflies 2020