Green Island, Poole Harbour, Dorset

Guide price: £2.5million

Estate agents: Stephen Noble (telephone 01202 557 766); Savills (0207 409 8887)

A secluded, private island has come up for sale just off Sandbanks, the south coast?s ?Riviera?, in Poole harbour.

Green Island extends to just less than 20 acres at high tide ? 45 acres at low tide – and is one of the five islands in Poole Harbour, the largest and most famous of which is Brownsea Island.

Thanks to the island?s rare fauna, which includes roe deer, red squirrels and 96 different varieties of bird, and flora, including Dorset heathland and rhododendrons, it has been designated as an Area of Natural Beauty (AONB), Site of Special Scientific Interest (SSSI) and Special Protection Area (SPA).

The current owner, Jo Davies, bought Green Island in 1987 for around £600,000 and has been running it as a wildlife sanctuary and holiday retreat for disabled and disadvantaged people.

There are just two buildings on the island. The main house is a wooden, A-frame hideaway with two bedrooms, situated out of sight in a secluded grove. The second building is bungalow called ?Greensleeves?, which has planning consent for development as a 2,000 square foot house.

The handling estate agents, Stephen Noble in Poole and Savills, have set a guide price of £2.5million for the property, but larger offers are expected.

?This is an extraordinary opportunity to acquire one of the very few private islands off the South Coast of England. [The island is] easily accessible by way of a short and easy boat ride from Sandbanks, [an area] where residential property values are some of the highest in the country. And with the new Bournemouth International Airport nearby, we are expecting considerable interest in this highly unusual property,? said Nick Sweeney of Savills estate agents.