INFORM your peers that you are heading for Boston and they may well recommend an itinerary on the New England heritage trail. 'No,' you say, 'not Boston Mass, Boston Lincs.' Blank looks all round.

Lincolnshire has become Britain's great unknown county, a giant, anonymous slab of parsnip-growing greenery, east of the A1 between the Wash and the Humber, to be rushed past on the way to somewhere else. Most people know only one thing about the county - that it is as flat as a pancake from corner to corner. It isn't, as it happens, but it's hard to convince anyone of that.

The local Lincolnshire council rather desperately entitles its guide for tourists The Secret's Out. Actually, it isn't. I went there in July, in glorious weather, and judging by the lack of humanity, the secret was definitely in. Try as it might, Lincolnshire is hopelessly, irrevocably unfashionable, and is much the better for it.

This lack of vogue is relatively recent. Once upon a time, Lincolnshire spelt money and power - largely through the twin assets of sheep and ships.

Many of the first British to colonise America came from this county. John Smith, from Louth, a former pirate, became president of Virginia. The Pilgrim Fathers used his charts on their voyage across the Atlantic. And Sir John Franklin, who died looking for the Northwest Passage, was born in Spilsby.

Later, Lincolnshire dissenters followed them to the colonies, landing at Naumkaeg in 1630 and renaming it Salem, before moving south to Trimountain, which they renamed Boston.

That other Boston is a place of prettily packaged history, with a well-kept old town and heritage trails. Boston Lincs has declined to play that game. Eating in a local Chinese restaurant, I asked the waiter what there was to see in the town. He giggled. 'In Boston?' he asked.

That's Lincolnshire all over: undersold, underpopulated and happily underdeveloped. It is a vast county, the fourth largest in England, and liable to swallow up the unwary visitor who tootles in by car imagining he can cover it all in a weekend.

Leaving aside the city of Lincoln itself, you will get the most sights per square mile in the eastern, coastal half of the county, running north from Boston. In this manageable chunk, there is a surprising array of points of interest: attractive old villages; the rolling hills of the Lincolnshire wolds; vast, empty coastal nature reserves.

Boston is an excellent place to start. The town sits just north of the Wash, overlooked by the landmark of 'the Stump', the tower of the parish church of St Botolph's, which is visible for miles across the surrounding fenland. If you are feeling brave, you can climb the tower to an open gallery, which, on a clear day, overlooks a third of the county.

The surrounding narrow streets retain great charm. On Fish Hill, fishmongers still sell crab and brown shrimps from the chilly waters of the Wash, and there is a happy clutter of old pubs where the price of a pint will surprise you. Lincolnshire is cheaper than most northern coastal areas. In the friendly little Ship Inn, a half of good beer and freshly roast beef in a roll almost a foot long cost me a little over pounds 2.

The town's other main sights are the 15th- century Guildhall, now a museum with the cell where the dissident separatists were incarcerated, the rebuilt timber Pescod Hall, and Blackfriars theatre and arts centre, once part of a Dominican friary.

The A52 leads from Boston towards the obvious base for any east Lincolnshire break, Skegness. In spite of the ra-ra atmosphere, the jolly fisherman emblem and its claim to being 'so bracing', Skegness is an inoffensive resort. The seafront is overrun with amusement arcades and fairground rides, but the neon soon peters out into a fringe of inexpensive B&Bs.

On the edge of town, the Vine Hotel - an old country house once supposedly used by Alfred Lord Tennyson, who was born nearby - charges half the price of hotels elsewhere for beer that is twice as good. The owners are those diehard heroes of the real ale brigade, the Bateman family, based in a fragrant old brewery on the edge of Wainfleet All Saints, a few miles outside Skegness, off the Boston road.

Bateman's boozers are dotted across the county and are usually unspoilt, friendly places where as little as 99p will buy you a pint of some of the best beer in England. If you are feeling adventurous, try to track down the rare Salem's Porter, a dark draught stout, a little like a real ale Guinness.

South of Skegness, a good walk from the Vine Hotel, is Gibraltar Point, a vast nature reserve of sand dunes that roll flat and inviting as far as the eye can see. No English county can match Lincolnshire for sand dunes. They march towards the horizon, a thin mist of golden sand blowing between the tufts of grass. Gibraltar Point is probably the busiest of all, but you're unlikely to bump into crowds on its 1,500 acres of beach, dune and salt marsh. Drive along the A1031 further up the coast, pass the caravan ghettos of Ingoldmells and Mablethorpe, and you reach the Saltfleetby-Theddlethorpe Dunes National Nature Reserve, a thousand acres of tidal flats, dunes and marshland.

Alford, with its weekly Friday crafts market, is probably one of the busiest of a handful of inland rural towns. Spilsby, Horncastle and Woodhall Spa are attractive little spots, surrounded by modest attractions, from goat farms to the home of the Battle of Britain Memorial Fleet. A little study and some of the excellent tourist leaflets chart a network of walks and well-planned cycle trails.

The bike is an ideal form of transport. Take your own machine, though; there are few opportunities to hire. The terrain is flat and the most common traffic you will find on Lincolnshire's country lanes is a lumbering tractor heaving spuds from field to farm.

Of the inland towns, Louth, to the north, is easily the most attractive. The centre is an amiable hotchpotch of medieval streets, enhanced by pretty old shopfronts. You can pick up a perfect pork pie in a real local butcher's shop, lounge in a pub garden, and wander around the stately St James's Church, all just a few minutes from the town centre.

In the New Market Hall, a development that puts most urban markets to shame, a huge cup of splendid espresso cost 60p, while a few yards away a fish merchant skinned fat, fresh cod for the slab.

West of the town lie the Wolds, bold, undulating hills that run from close to the Humber to south of Horncastle.

From Nob Hill, on the top of the Wolds, on a clear day, you can gaze across to the coast at Skegness and the towers of Lincoln Cathedral, and finally forget all notion of Lincolnshire being entirely flat.

Near the end of the drive is the little village of South Thoresby, next to the Swaby Valley, where two manageable walks should convince any remaining doubters. In the valley you can find five species of orchids, and an abundance of birdlife, from snipe to finches and tree creepers. Grayling and trout swim in the becks, or streams, that crisscross the valley. Once, South Thoresby was a large, busy village, with five pubs. Now only one, the Vine, survives, but that has inexpensive rooms and good home-cooked food.

Apart from huge breakfasts with excellent local sausages, eating is not high on Lincolnshire's list of priorities. As one downcast would-be restaurateur told me: 'The greatest compliment you can get is 'it covered my plate'.'

On my last night, in the otherwise wonderful Vine Hotel on the edge of Skegness, I rashly asked for a mixed salad with a steak. Two limp lettuce leaves duly arrived, with a couple of spring onions, a boiled egg, a sprinkling of cress and - in pride of place - an enormous pickled onion, carefully sliced to the core, with small petals of radish neatly slotted into the cuts. The waitress watched me struggle with the meal, removed the half-full plate, then wheeled on a trolley laden with mountains of chocolate and cream and announced, 'Pudding of the night is rigor mortis by raspberry.' I suspect Lincolnshire may remain happily unfashionable for some time to come.

The Vine Hotel, Skegness (0754 763018) from pounds 44 for an en suite double room, two nights with dinner, bed and breakfast pounds 70 per person.

The Vine Inn, South Thoresby, near Alford, tel 0507 480273, pounds 15 per person, including breakfast.

Tourist information: Boston (0205 356656), Skegness (0754 764821), Louth (0507 609289), Alford (0507 462143). Lincolnshire County Council publishes a range of maps covering walks, cycle paths and special interest trails (0522 552821).

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