On 1 April, Rutland is resurrected. Stephen Wood visited England's smallest county - home of Europe's largest man-made lake, and venue for a modest version of the great outdoors
As of next Tuesday, England has a new tourist destination, at the heart of the country. Perhaps "new" isn't quite the right word. But it is certainly true to say that nobody has visited the county of Rutland for the last two decades, because it ceased to exist in 1974, becoming merely a small part of Leicestershire.

Now, thanks to the Local Government Commission, the Rutlanders have won back their independence, and the born-again county has resolved to exploit its "outstanding potential ... to attract both funds and people to Rutland to boost tourism".

Like most small things, Rutland (which, at 39,398 hectares, is one-20th the size of North Yorkshire) has always had a job to be taken seriously. In the Seventies, particularly, it suffered at the hands of the former Monty Python member Eric Idle, with his Beatles spoof The Rutles, and the Rutland Weekend Television comedy programme.

The fact that Rutland Independence Day falls on 1 April suggests that it could just be a joke, a suspicion heightened by some of the associated "Rutland Celebrates" events, which include a "Made in Rutland" craft fair on Monday and a special National Childbirth Trust coffee morning on Wednesday. So I checked the local press (Rutland FM wasn't broadcasting at the time). I know you can't believe everything you read in the papers, but if Rutland's independence is a joke, the Rutland Mercury and Rutland Times are in on it.

The last time Rutland was a county, its motto of multum in parvo ("A lot in a little") was something of an empty boast, as far as the tourist was concerned. Less so now, though - thanks to Rutland Water. This is not a commodity available lightly carbonated on supermarket shelves, but a leisure facility.

True, people in the surrounding counties and as far south as Milton Keynes do drink the stuff, because the 3,100-acre man-made lake - the biggest in Europe - was created in 1976 as a reservoir for Anglian Water; but for Rutland the 27,300 million gallons are its prime tourist attraction, offering a wide variety of watersports, fishing and cycling (on the waterside path), plus a museum, garden, nature reserves, a butterfly and aquatic centre - and boat trips across the lake.

When I visited Rutland, it wasn't great outdoors: on a cold, cloudy and windy day, the idea of a careful study of the collection of old agricultural implements in Rutland Museum, in the county town of Oakham, seemed more attractive than going down to the lake. This weekend, things pick up there: the steam engines are running at the railway museum near Cottesmore, the Rutland Water museum in Normanton Church is open, and Rutland FM is broadcasting. But before Easter all of them were closed.

So after checking out the museum, and Oakham itself - a rather dull market town apart from the area around the Buttercross, with the "castle" (a fortified Norman manor house), the church restored by Sir George Gilbert Scott, and the school - I drove down towards Rutland Water, under a vast, lowering sky in which RAF Tornado jets from the Cottesmore base played tag, and through the picture-postcard, stone-built village of Exton.

Whitwell, on the northern leg of the U-shaped lake, is a more cosmopolitan place than it looks. Unaccountably, the village is twinned with Paris (yes, the French capital - I asked); and down by the lake at the Surface Watersports centre, the little Topper dinghy I hired for an hour was rigged for me by Rui, from the Algarve. (Again, I asked - and it was his wife's microbiology course at Leicester University that had brought him here, rather than the international reputation of Rutland.)

The watersports centre is, surprisingly, open all the year round; but it wasn't doing good business in mid-March. There were a handful of windsurfers out, but only one other dinghy.

Having no change of clothes, I resolved not to end up (as I did the last time I sailed here) in Rutland Water; but the wind was whipping up waves big enough to bring the water into the dinghy, and through the "waterproofs" I had borrowed. Dampened, I pushed on - at speed - along the southern leg of Rutland Water to Nether Hambleton. Not that there was anything to see there. Never has "nether" been more appropriate - the village vanished beneath the lake 20-odd years ago.

The nearby cycle hire shop was doing slightly brisker business than the watersports centre, and I met a couple of other cyclists on the gravel path that runs around the lake. Twenty-five miles long, it passes the nature reserves (with 13 bird hides) to the west, and Normanton Church museum to the south, then runs along the dam - a massive stone rampart that looks like a grand version of the "land art" exhibited by Richard Long in the Tate Gallery - which closes the lake to the east.

Along its north shore, the lake connects the main recreational areas, including the butterfly centre (then closed, now open) and the "drought garden and arboretum".

The garden, which fortunately for me is open all year, is sited on a dry, south-facing clay slope, and has survived for 10 years without ever having been watered, thanks to techniques such as planting ground-covering plants to retain moisture. It's rather a sweet place, looking good even in mid-March; but there is something peculiar about a drought garden within sight of 27,300 million gallons of water.

My day's exercise over, I drove around the Hambleton "peninsula", which sticks out into the lake. Here are the highly rated Hambleton Hall hotel and restaurant - it looks very grand, so I didn't go inside in my damp jeans - and the southern gateway to the huge Palladian house of Burley- on-the-Hill, built by the second Earl of Nottingham in the late 17th century. Through the gateway, you can see the house a mile-and-a-half away at the end of the drive; but when Rutland Water is high you can't see the drive, because it is submerged.

On the way home I stopped at Uppingham, Rutland's second biggest town (pop: 3,679).

Much more attractive than Oakham, it has a perfect little market square that might have been built especially for a Merchant-Ivory production, with the right sort of businesses (The Vaults pub, The Falcon Hotel, antique and hardware shops, a post office) all nestling behind ancient facades. The Chinese take-away is an exception, but - as I discovered on a lonely night in Uppingham last year, the food is exceptional, too.

Multum in parvo? Not really, at least in mid-March, but enough to have earned Rutland a remarkable pounds 11.2m from tourism last year.

Dinghy hire on Rutland Water costs from pounds 7 per hour; bicycle hire, from pounds 4.95 for three hours.

Rutland tourism information, 01572 724329; Rutland Water Tourist Centre, 01780 460321.