But until I went to Sicily 20 years ago, I suppose the nearest thing to a sculpture park I'd seen was Trafalgar Square. Yet there, just above the coastal backwater of Castel di Tusa was a whole hillside of al fresco sculpture paid for by one man, Antonio Presti, son of a wealthy cement-manufacturing family who believed that art belonged in the community, whether or not the community wanted it.
We've come a long way since then. When Birmingham city centre was pedestrianised in 1993, Victoria Square was designated a public art space with a range of works commissioned from the Indian sculptor Dhruva Mistry. His centrepiece was River, a chunky stone nude, semi- abstract and reclining in a fountain. Soon nicknamed "The Floozy in the Jacuzzi", River quickly came to symbolise Brum in a way that Queen Victoria, on her plinth nearby, never had. Suddenly, it seemed British public sculpture didn't have to be monumental any more. Since then we've seen some huge pieces of community art. In 1998 Antony Gormley's massive The Angel of the North appeared in Gateshead; and in 2001 motorists queuing on the M5 were given Serena de la Hey's Willow Man to look at. The same year saw Anish Kapoor's six-metre-high Sky Mirror, unveiled in Nottingham city centre, amid talk that it would have to be shielded from the sun if passers-by were to avoid being blinded.
But the really big step forward was the grouping of individual sculptures into purpose-built display areas. Since its opening in 1970, London's Serpentine Gallery had had a small outdoor area, but for many years Britain's premier sculpture parks were the homes of Henry Moore and Barbara Hepworth, two major 20th-century artists who had taken to displaying their own works in their gardens.
Hepworth's St Ives home was opened to the public in 1976, after her tragic death in a fire, and is now administered by the Tate Gallery. Moore's estate at Perry Green, Hertfordshire, extended over 70 acres at the time of his death in 1986, but, because he was worried about huge death duties, it had already been passed over to the Henry Moore Foundation in 1977, with tours for the public by appointment.
In recent years, however, the curating initiative has passed to individual collectors and entrepreneurs. In 1993 Madeleine Bessborough moved the New Art Centre, her London gallery, to Roche Court, her Wiltshire home, where she has continued to promote the work of recent British sculptors. Two years later Wilfred Cass, a retired businessman, opened his sculpture garden in the Goodwood estate in West Sussex. Today it contains 72 pieces, all of them commissioned by the eccentric, art-loving Cass. All of them are for sale.
One of the costliest of Cass's exhibits is by Lynn Chadwick, an early pioneer in modern public statuary, and the controversy that often surrounds it. In 1958 Chadwick had his memorial to the Air League of the British Empire memorial, Stranger III, written off by the league for resembling "a diseased haddock". Fortunately, Chadwick made four copies before his death in 2003. Three of these are now displayed abroad (in Italy, US and Belgium) and the fourth is now at Goodwood. It stands in a clearing, looking more like a flying horse hiding underneath a large tarpaulin than a haddock, but these things are always subjective.
Cass also exhibits work by Tony Cragg, whose Bent of Mind looks disturbingly like a hangover, and whose silver sperm sculpture, I'm Alive, gives the impression that it could coil round at any moment and lasso you. He has also bought Antony Gormley's penis-shaped bollards (commissioned and rejected by Peckham Council), which have been put to practical use in the garden.
There is something unique about an open-air sculpture garden which simply cannot be found in any other arts installation. First, there is the element of unpredictability. You never know when you are going to come round a corner and encounter a display. Second, the context can be startling. In the Hannah Peschar Sculpture Garden in Surrey, large blue tubular damselflies hover on metal spikes alongside a real stream, while in the Yorkshire Sculpture Park, near Wakefield, Winter and Hörbelt have built a two-storey steel pavilion, Oxley Bank, which is both a work of art in itself and a framing device for looking at Longside Valley below.
At Roche Court I was struck by Barry Flanagan's acrobatic hares, rearing up 30ft above the visitor, and Tony Smith's inexplicable black Wall which lies, like the monolith from Stanley Kubrick's 2001: A Space Odyssey knocked on its side, halfway across a field.
That most of these parks are privately funded says a lot about individual enthusiasm - and perhaps institutional suspicion - towards sculpture gardens in Britain at the moment. But they continue to grow in popularity. On Guernsey, Peter de Sausmarez has created a labyrinthine trail through the grounds of Sausmarez Manor in order to display 220 works of art lent to him by UK artists. "We started in 1998. I was scratching around for some way to encourage more people to come," says Sausmarez. "We sell the pieces for the artist. About one third go locally, one third to the rest of Britain, and one third abroad. We find we get more and more people coming every year."
If he's still over there in Castel di Tusa I think Mr Presti would be impressed.
For further information on sculpture parks visit Outdoor England (enjoyengland.com/outdoor)
Where to go for heavy rock
The New Art Centre Sculpture Park and Gallery
Roche Court, Salisbury, Wiltshire (01980 862244; sculpture. uk.com). 100 acres. Works by English sculptors, post-1950, including Gormley, Caro, Frink, Alison Crowther, Richard Deacon.
Kensington Gardens, London W2 (020-7298 1515; serpentinegallery.org). Three acres. Founded in 1970 by the Arts Council of England. Changing shows. Admission free.
Yorkshire Sculpture Park
Bretton Hall College, Wakefield, West Yorkshire (01924 830579; ysp.co.uk). Two hundred acres of parkland, featuring its international collection and works by Caro, Hepworth and Moore. Admission free, parking £3.
Henry Moore Foundation
Dane Tree House, Perry Green, Much Hadham, Hertfordshire (01279 843333; henry-moore-fdn.co.uk). Twenty-five sculptures by Henry Moore in the grounds of his former home and studio, above. Admission £10, by appointment. Closed until April 2006.
Barbara Hepworth Museum and Sculpture Garden
Barnoon Hill, St Ives, Cornwall (01736 796226; tate.org.uk/ stives/hepworth.htm). Permanent Hepworth collection, more than 40 works dating from 1950. Admission free.
Ironbridge Open Air Museum of Steel Sculpture
Moss House, Cherry Tree Hill, Coalbrookdale, Shropshire (01952 433152; go2.co.uk/ steelsculpture). Ten acres with more than 60 sculptures, including many by steel sculptor Roy Kitchin. Admission £2.Reuse content