Rosamund the Fair, once upon a time famed as the most beautiful woman in Christendom - before she became a nun in Godstow - must have been a familiar figure on the banks of the Thames in medieval times.

Her namesake - a 72ft narrowboat with a restaurant on board - while perhaps not quite comparing with her in the beauty stakes - has carried off prizes including Most Romantic Restaurant from the Oxford Diners' Society, and a place in a list of Britain's top 100 restaurants compiled by BBC Worldwide Olive magazine.

But stop a minute, many an Oxford reader will mutter here. The floating restaurant was a familiar sight in summer, but she seems to have been been missing from the river scene recently.

The fact is that four years ago she moved up the Oxford Canal to Banbury where, ever since, she has continued to attract gourmet diners at weekends, or private parties during the week.

But now she is up for sale at an asking price of £120,000, and the hope is that she will return to Oxford. Her owners have found a city centre mooring for her at Hythe Bridge Street.

Owner Tim Matthews started Oxford's cruising restaurant, with a licence to carry 35 people including crew, 18 years ago, mooring her near the Trout, in Wolvercote.

As a distinguished chef himself, having worked at Langans in London and the Montreux Palace in Switzerland, he aimed to start a catering company with a difference, offering beautiful meals, using only the freshest materials, in beautiful places.

He said: "Sophia, now my wife, joined the business shortly after I began in Oxford. She began her training as a chef under Raymond Patterson in Cambridge.

"Our restaurant delighted the residents of Oxford for more than 12 years, as well as guests from all over the world, and she quickly gained a reputation for being the most romantic in Oxford - and also voted one of the top 100 restaurants in Britain - all from a 6ft x 9ft galley!

"She is a restaurant that moves; not a boat that serves food."

He added: "There are many many fascinating stories about Rosamund from over the years. So it's sad that we have decided to sell her."

The reasons for that decision date back to 2003, when the Matthews' company, Rosamund Catering, won a bid to run a historic boatyard in Banbury called Tooley's, which contains Britain's oldest dry dock.

Mr Matthews said: "Now, sadly, since we are now based in Banbury, Rosamund just doesn't fit with the business that has developed.

"And really I would like to see her move back to Oxford, where she belongs."

And how has the business developed? At Tooley's, Matthew Armitage, who trained under Bill Boswell, one of the last canal men in Oxfordshire, and who was boat master of Rosamund for ten years, runs tours, a chandlery, a boat school - and an original working forge.

Mr Matthews happily admits that his interest in Tooley's, and in all things to do with inland waterways, came about as a direct result of his love for Rosamund the Fair.

But true to original principles of producing beautiful food in beautiful places, he also runs the Cafe Quay, a modern canalside cafe below the Banbury Museum, with Rosamund moored up alongside.

The floating restaurant, despite being up for sale, still treats weekend diners to a four-course meal, plus coffee, plus a two-and-a-half hour cruise, at £52 each.

And now Rosamund Catering is diversifying again. Its newest venture is to start the Carriage Restaurant in the courtyard of the National trust property Claydon House in Buckinghamshire. This was the historic home of the Verney family and once also home to Florence Nightingale.

Mr Matthews said: "Our new chef Chris Hand uses local fruits and vegetables, many from the garden at Claydon."

As for the original Fair Rosamund - meaning Rose of the World - she was the mistress of Henry II, whom she used to meet at Rosamund's Well (which still exists) near to the Royal Palace of Woodstock, that stood close to the present Blenheim Palace.

She was revered almost as a saint and the fable grew that the king kept her in a labyrinth at Woodstock to protect her from his jealous Queen.

All to no avail, however, as Queen Eleanor tracked her down and had her murdered after following a silken thread attached to her dress through the labyrinth.

In fact, Rosamund almost certainly died at Godstow, the nunnery on the banks of the Thames, near the Trout Inn, where the floating restaurant was originally moored.

Here's hoping she will soon be back home in Oxford.

Contact: Rosamund Catering: 01295 278690