English people go to Calais for only two reasons: to pass through it on the way to somewhere else, rather nicer, in France; or to load up enormous white vans with duty free goods and bring them back into England swearing to suspicious customs officers that they are all for personal consumption and that the driver, personally though completely sober at the moment, has usually downed two cases of wine and four thousand cigarettes by this time of day.

I wanted to go to Calais for the purpose of research: into history. My husband wanted to look at French bathroom taps. With a synchronicity such as this we could do nothing but be happy for three nights together in Calais.

We started with the historical research. As any school child knows and some adults remember, Mary Tudor - Bloody Mary - is said to have died with the world 'Calais' carved on her heart since it was during her reign that the English castle of Calais was lost to the French and never regained. It was the end of England as a continental power, and the birth of our view of ourselves as an island, and then an imperial peoples.

I am writing a novel set at the tense and claustrophobic court of Mary Tudor, where the Queen, bedevilled by her passion for her husband, King Philip of Spain, her own infertility, and her desire to restore England to the Roman Catholic faith, moves inexorably from the adoration of her people to their bitter enmity.

She called herself the 'Virgin Queen' before her marriage, she promised she would be married to her people. Her envious and brilliant half sister Elizabeth watched and learned. Mary's mistakes were Elizabeth's education.

It's been a fascinating novel to write about a Queen too little known, a woman whose nickname 'Bloody Mary' forever condemns her to the cartoon view of a bad English Queen, and neglects the complex and interesting woman.

She was the daughter of Katherine of Aragon, the surprise heroine of my novel The Other Boleyn Girl, a woman who just walked towards me, out of the research and off the page, because of her dignity and loyalty as her husband betrayed her with another woman, and then tried to set all of Europe against her to get his utterly illegitimate divorce. I had expected Anne Boleyn to excite me and inspire me with her mixture of ambition, sexual manipulation and political astuteness. I knew that I would love to research the story of the unknown Boleyn girl: her sister Mary. But I had not expected to feel such admiration for Queen Katherine, and to find the same qualities of staunchness and courage in her daugher, Mary Tudor.

I always visit the settings of my novels. Often, this is the only place that I can get the details of historical research, the little booklets of local history, or even the surviving geography which makes the research come alive. At the very least, I can experience the atmosphere of the real place: the ambience, the quality of the light, the colour of the earth, and the smell of the streets.

'Why not do a novel about Captain Cook?' my husband suggested helpfully. 'Pacific, South Seas, Australia. We could visit there.'
'Mary Tudor,' I replied firmly. 'Calais.'

And so we found ourselves embarking on an extensive railway tour. GNER from our home in the north of England to London, taxi to Waterloo, and then the beautiful Eurostar train, sleek and white as a sucked ice pop, from Waterloo to Calais Frehun. The train was half-empty, we travelled in style, we sipped champagne and ate something elegant, we arrived at a spankingly modern beautiful train station of Calais Frehun and got out to…. Nothing.

Not a bus, not a taxi, certainly not a town.
'Where is it?' I asked, demonstrating my spirit of academic enquiry.
'Miles down the road,' he replied with the quiet certainty of a man brought on a wild goose chase and left in the middle of a French intersection by a wife whose history is better than her geography.

Eventually we got a taxi to the town centre and to our hotel the George V. As the name suggests, the port has remained a big fan of the English. Their trade and travel focus has stayed cross-channel, and the town was liberated by Allied forces at the end of World War 2. They kindly say liberated, meaning that the enemy went away; but in fact the port was pretty thoroughly squashed by bombing and bombardment, with the result that the old walled mediaeval town with its gun emplacement gateways and canals has been completely obliterated.

This was a bit of disappointment to this particular eager historian, but at least the tourist information office had a selection of booklets which have photographs of the old town, and maps of the English 'Castill of Callis'. But better than all of that, when I told them that I was researching my novel, set partly in Calais, they gave me the telephone number of a local historian, Monsieur Fauquet.

Monsieur Fauquet turns out to be the pivotal point of this research trip. A dapper, short Frenchman in a bright houndstooth tweed coat, he was history professor at the university before his retirement, and now is the acknowledged expert on Calais history. He knows everything there is to know about the history of Calais in theory and in practice. He is an academic but also a descendant of the notorious Calais corsairs - pirates that ravaged the channel trade, and as a child of this town he remembers it's old beauty, before the wartime destruction. I flipped open an eager notebook and bombarded him with questions which he answered in perfect English.

As we left, he produced a copy of my book The Other Boleyn Girl, and as I signed it for him, he told me that even in France they saw the recent BBC film of the book and that he enjoyed it. We parted in mutual admiration: him to his studies and me to look at taps.

Shopping in Calais itself is sadly, not to be recommended. The town has basically one main street which has some less than enticing clothes shops, a few souvenir and knick-knackery shops, and, in typically French style, amid this scarcity of opportunity: some restaurants and cafes to die for. That first day we went for a late breakfast and had hot chocolate and a croissant, meltingly flaky and sweet. That lunchtime we ate simply but deliciously: an omelet natur and a glass of the local beer. Heaven. That evening we dined in the restaurant of the George V, a meal initiated with a glass of champagne and a tiny delicate tray of appetisers, starring the most delicious roast duck I have ever eaten in my life, and accompanied with a bottle of wine which tasted like melting flowers on the tongue and lingered like a kiss.

Enough with the food and sex! But what about the taps? There are two areas to eat in Calais: either on the one main street, or head out to the beach for seafood specialities; anywhere is wonderful. But the place to shop in Calais is Auchun, an out of town experience as aesthetically ugly as anywhere else in the western world, but a real spirit-lifter for retail therapy. We looked at taps, and lights, and paving, and then we recalled the great disadvantage of doing a trip such as this by train: not even I with my enthusiasm for French style was going to carry taps and paving slabs and a delightful stone circular table with circular bench, a couple of deck chairs and an amusing bathing-hut wardrobe, on the Eurostar train and across London to Kings Cross. So we priced them: (good but whether it is in Euros or pounds, quality still costs) and promised to come back with the car, or even a white van. Then we strolled into the Nike shop and I fell in love with a couple of pairs of trousers, and fell again when I discovered I was 'petite', and we both fell at the till when - allowing for the 20% sale price I had two pairs of delightful trousers for £30. Better than Matalan, and who can say more than that?

On our second day we visited the museum where we greeted the exhibition of modern and experimental art with our usual aggressive disbelief, and I pored over a scale plan of the town of Calais before the war where at last I could understand the street plan, and the encircling moats of the canals. The Tudor town, half-lost under (17th and (18th fortifications and then lost forever in a hail of bombing, starts to shine in my mind. The busy fishing harbour where half the boats are privateers, preying on the rich Channel trade, the cobbled streets leading to the great English building the 'Staple Hall' where the merchant oligarchy that runs this town does its business. The continual flow of trade to and from France and England, but also Flanders and England, through Calais, with Spanish owned Netherlands as another player in this north European game of shifting borders. The great castle which takes up five acres in the very centre of town, the great walls and the towers and gates which close at dusk and open at dawn. And outside the odd culturally mixed English Pale which has been under English rule for two hundred years but was once France, and will be France again.

The magic which my writing creates for me, starts to weave its web in my mind, and I walk beside the canal in this rather dull, French town, and hear the broken accents of the English settlement, arguing over the duty on a fleece, haggling for a cheese, warning of a religious inspection. I stand outside L'eglise de Notre Dame, and wonder what the English called this church when they were Protestant English under Henry VIII, and when they were Catholics under his daughter, Mary Tudor? Above me, the ornate church doors, as French as the cathedral of Rouen, soar up to a tower of staunch English Perpendicular, which still stands, despite the (16th French siege, despite a later earthquake, despite in the (20th : the German siege, and then the Allied bombardment.

There are undoubtedly prettier towns in France, but none so close to England, geographically and historically too. And for me, an historian day tripper with a taste for good wine and food and a liking for little out-of-the -way places; if Paris is worth a mass, then Calais is worth a train ticket.