Friends, and now business partners, Rosemary Fennel and Margaret Anderson have just published the third book in a series devoted to finding the very best French markets.

Rosemary, a retired Oxford academic said: "We have been travelling together to France since 1976, and fell in love with the markets down through the years.

"We thought it would be helpful to have a guide to know what's on when, and where. It's quite infuriating to turn up for a market to find that it was held the day before."

With all these considerations in mind, Margaret and Rosemary vowed to one day compile a book about the best markets they came across.

"In 2001, we were both retired, so we either had to do it, or shut up about it," Rosemary laughed.

Last year, the fruits of their labour appeared in the form of two books: Best Street Markets in France: Dunkerque to the Somme, covering the coastal towns of Dunkerque, Calais, Boulogne, and Le Touquet, and their hinterlands, and Le Havre to the Somme covering the coastal towns of Le Havre, Fcamp, Dieppe and St-Valery-sur-Somme, and their hinterlands.

Dedicated to making life easier for any avid market-goer, or indeed just your average traveller or day-tripper, the books not only select the best of the bunch, they rate the markets, tell you when they are on, and point out other places of interest in the towns.

The duo's latest offering covers Honfleur to the Cherbourg peninsula, which includes the coastal towns of Honfleur, Caen, Granville, and Cherbourg, and their hinterlands.

"We publish the books ourselves, and sell them mainly through our website," Rosemary explained.

But what is it about the markets that makes them worthy of three books, with a fourth coming out next autumn?

"The variety and quality of the goods. You just don't find it here."

Stocking everything you might expect - fruit and veg, cheese, cooked meat and pastries - the markets also have a wide range of goods you might not, such as shoes, clothes, jewellery, and household items. In short, everything but the kitchen sink.

Starting at the north-west coast of France, the women initially choose this area as it was the closet to England - and perhaps the most popular with British tourists.

Now they are moving down the coast, as Rosemary says, in a logical progression.

"Our academic background is useful for something in all of this," she laughs.

Indeed, organisation is paramount to the process, and with the fourth book due out for this time next year - covering St Malo to Brest - there is no time to waste.

"People always say the research must be good fun, but we are very regimental about it," said Rosemary.

"There are so many markets to get to, it is very time consuming. We try to get to three markets in one morning, then write it up straight away while it's still fresh.

"I get some funny looks as I walk around speaking into my tape recorder," confides Rosemary, "while Margaret takes the pictures."

Needless to say, some of the markets do not make the fastidious final cut.

"In this latest book we selected 35 out of 63, so we rejected about half."

All in all, each book consists of about six weeks research, and concentrates only on markets that are on all year around.

Still not convinced?

"The markets are so much more than just fruit and vegetables," Rosemary said. "They are full of surprises, and thoroughly sociable, and you don't need to speak French - they are used to tourists and will understand what you need."

Her passion for markets is still obvious after all her years of going: "It is an engaging pastime just to be there, you don't even need to buy anything - the special atmosphere is free."

And it is only a short sea trip, or a trip in the Euro Tunnel, and you've got an entirely different shopping experience.

With book number four in the pipeline, it has been an intensive few years for the ladies.

"It's been a steep learning curve, and a fascinating one at that, but I think we might take a year out after the next book," said Rosemary.

"But someone did suggest the south of France for our next series," she adds with a twinkle in her eye.