The Sentinel, the landmark mountain at the entrance to Hout Bay, is for sale.

An advertisement in the property press last week, entitled "buy a mountain with a sea view" has shocked many Capetonians who believed the Sentinel was part of the Table Mountain National Park.

But the mountain is privately-owned and is on sale for R12-million. Park staff have said it would be "an outrage" to allow any development on the Sentinel.

The owners of the 10,9 hectare property are a close corporation, G&R Marine Services. Sources say it was bought a few years ago for R50 000. The advertisement describes the Sentinel as "among the Cape's most photographed natural features".

The land is zoned rural, which allows one residence to be built on the land. The owners would need to apply for rezoning to be able to build more than one house.

Rainer Kloos, the estate agent handling the sale, said the owners appreciated that it was a landmark in the Cape. He said because of the steep topography, it would be impractical to rezone the land for development.

"It's quite unusual for a mountain to be up for sale. Whoever buys it will probably do so to be able to say: 'I own that mountain'."

Mike Slayen, SANParks property manager, said on Sunday: "It would be an outrage for any development to take place on that property. It should be incorporated into the park.

"We want to make it clear to any prospective buyers that they understand what they are buying and the severe constrictions to any development on this property because of the steep topography, its ecological sensitivity and because it is an icon."

Slayen said the Sentinel had been earmarked as a "priority piece of conservation land" by SANParks. It had made several offers to buy the Sentinel, all of which had been rejected.

"SANParks will take all steps necessary to ensure that the Sentinel is incorporated into the park. We advise all prospective buyers first to speak to us," Slayen said.

Andy Gubb, of the Wildlife and Environment Society of SA, said any attempts to develop the Sentinel would be met with fierce resistance from Capetonians.

"We will fight it tooth and nail. So much of the Peninsula has disappeared under concrete. Any remaining land outside the urban edge should go to a conservation agency," Gubb said.

Morne du Plessis, of the local branch of the World Wide Fund for Nature, said it would not want to see any development on the Sentinel - "not even a single dwelling".

"It is one of the icons of the area," Du Plessis said.

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