Some of the Trust's smaller reserves have restricted access to the public, perhaps because they can only be reached by crossing private land, or to avoid disturbance to particularly sensitive wildlife.
The Trust can, however, grant a special permit for interested parties to visit these sites – please call the Reserves Department on 01273 492630 for details.

Balcombe Marsh
A tiny fragment of marsh, near the village of Balcombe, surrounded by improved grazing pasture.
The tall fen vegetation contains meadowsweet, sneezewort, greater spearwort, angelica and many other typical marsh species including the last remaining colony of marsh helleborine in West Sussex.
The 0.4 hectare nature reserve is situated on a private estate.

Chailey Warren
Close to the Chailey Commons Local Nature Reserve complex of heathland and woodland, this reserve supports a good colony of marsh gentians growing amongst the heather and purple moor-grass. Light grazing with ponies for part of the year helps to keep down the bracken and birch seedlings, and provides some bare patches to give the gentians an opportunity to establish new plants.
This 2.8 hectare Site of Nature Conservation Importance is isolated and rather difficult to access, and can only be reached over private land.

The Deneway
Constituting part of the Withdean Woods Local Nature Reserve in Brighton, this is a narrow strip of embankment between the railway line and some houses. Largely secondary woodland, it provides a home for badgers, foxes and a variety of birds.
Due to its proximity to the railway there is no public access.

Hundredhouse Copse
Eight hectares of ancient woodland that form part of the much larger Binsted Woods complex, just south of the A27 between Arundel and Chichester. Composed largely of oak with a hazel under storey, there is a good variety of higher plants in the ground flora, as well as many mosses and liverworts.
There is no public access to the nature reserve itself which is privately owned and leased to the Trust, but a public bridleway runs around part of the boundary.

Leythorne Meadow
This delightful wet meadow just south of Chichester has a mixture of fen meadow and pasture communities, including southern marsh orchids. Occasional cattle grazing is an essential part of the management.
This 1.5 hectare Site of Nature Conservation Importance can only be accessed across private land.

Marehill Quarry
This 0.5 hectare geological Site of Special Scientific Interest near Pulborough is a small network of quarried underground tunnels which display particularly interesting clay and sandstone strata that are rarely seen at the surface. The tunnels are also important as a hibernating site for bats.
The nature reserve is closed to prevent disturbance and for public safety.