Hilsea Lines

This valuable nature area has developed on a site that was originally a military base.

The first defences, built 1544, protected the city and port of Portsmouth from inland attack for 300 years, before the existing Lines replaced them in 1871 when the renewed threat of a French invasion prompted the construction of stronger defences.

This two-mile long structure of chalk and earth ramparts 9m high and 20m wide, has six bastions of bombproof casemates and a moat to the north. The expected invasion never happened  and Hilsea Lines have never been used in battle.

Most of the original structure is unaltered today. The Lines were designated a Scheduled Ancient Monument in 1964, and gained Conservation Area status in 1994 in recognition of the value, not only of the monument, but also of its setting.

The site of Hilsea Lines has become the most varied wildlife haven on Portsea Island, containing within its 80 hectares woodland, hedgerows, meadows, both fresh and brackish water areas, marshland and coastal habitats. Here is a small selection of the wildlife to be found here:

• mammals and birds – Field Vole, Kestrel, Dunlin, Kingfisher
• reptiles and beetles – Smooth Newt, Stag Beetle
• butterflies and moths – Small Tortoiseshell butterfly, Garden Tiger Moth, Emperor Dragonfly – the largest British dragonfly
• flowers and plants: Lords and Ladies (Cuckoo Pint), Bee Orchid, Yellow Flag, Common Walnut Tree (not native to Britain but were planted in this area by the military to be used for rifle stocks and butts).

The moat at Hilsea Lines, originally a single body of water, is now divided by a series of footpaths and bridges into four separate areas. These range from a pure seawater lagoon near Hilsea Lido with a good variety of crabs, shrimps and eels to two freshwater moats whose natural vegetation affords excellent wildlife habitats for water birds and insects.

The freshwater moats are used by Portsmouth and District Angling Society. Contact them direct to find out more about fishing at Hilsea Lines.

The final moat is brackish water. This moat has an interesting contrast of habitat to the other moats and has flora and fauna that have adapted to the partially salty conditions.

A Countryside Ranger oversees the day-to-day care and protection of the Hilsea Lines Conservation Area and all the wildlife habitats. Portsmouth City Council’s long-term plans for the area are documented in the Management Plan, which can be downloaded below.

The Hilsea Lines Ranger runs a healthy volunteer programme for anyone interested in participating in the valuable conservation and restoration tasks. For more information about the opportunities for volunteering, phone the Ranger on 07958 353152 (answerphone facility) or email parks@portsmouthcc.gov.uk.

The Hilsea Lines Ranger is based at Bastion 3, Scott Road, Hilsea.

Due to the outdoor nature of his work, there is no guaranteed time he will be in the office, so it may be advisable to telephone first.

• Telephone 07958 353152 (there is an answerphone)

• Email parks@portsmouthcc.gov.uk

There are Interpretation Boards throughout Hilsea Lines that highlight self-guided walks and emphasise some of the nature and history that can be seen along the way.

The leaflets available below are useful for self-guided walks.