What it is: A ruined second world war early warning radar station at St Boniface Down, near Ventnor, that was instrumental in detecting Luftwaffe attacks during the first month of the Battle of Britain. However, on August 16, 1940, it was hit by a bombing raid, becoming the only radar station to be badly damaged during the war.

The station was one of 21 “East Coast Type” radar stations built in 1937-8, running along the coast from Ventnor on the Isle of Wight to Netherbutton in the Orkneys. It initially had four (later three) 350-ft high steel transmitter towers.

The 3.7-acre site, now owned by BT, includes two former operational buildings and a disused radio mast, and goes to auction at the Berkeley hotel, London SW1, on Tuesday afternoon.

The problems: Abandoned, overgrown and covered in downland grass, gorse, nettles and bracken, the package comprises its acreage and the buildings, one a concrete bunker. The local planning authority has indicated that it will resist any residential development proposals. Located just off a road, access is easy, and there are services nearby, but the most development you are likely to be granted is for storage. “People think, ooh, fantastic, a building plot, ” says the auctioneer, “but really it’s a couple of acres of land with no prospect of development in the near future, not even as a futuristic sunken home.”

The advantages: The very reasons that make a building permit unlikely: it is in an area of outstanding natural beauty, is a site of importance for nature conservancy and adjoins a site of special scientific interest. Realistically, it is nothing more than an expensive picnic spot, albeit one with spectacular views across Ventnor and the English Channel. The last similar site sold by the auctioneers was a former control tower in a six-acre plot with no planning permission on the Kent coast. It sold for £61,000 in 2001 from a guide price of £20,000. In investment terms, you need to take the long view.

Allsop & Co auctioneers, 020 7543 6710, www.allsop.co.uk; Isle of Wight district council, 01983 821 000, www.iwight.gov.uk

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