Just remember one thing, The Da Vinci Code is a work of fiction. Yes, it does explore the most fascinating myths and legends but they are all subject to author Dan Brown’s imagination. Lesley Bellew found out just how far that stretched by jumping on a Eurostar train to Paris.

THE monks at Saint-Sulpice would not sell out to Hollywood so The Da Vinci Code director Ron Howard (you may remember him as the red-headed Ritchie in TV’s Happy Days) had to improvise.

He was probably not best pleased as the Jesuit-style church – the largest in Paris – possesses a haunting atmosphere and light, created by centuries of upheaval and rebuilding, that would have been difficult to recreate.

Considering Dan Brown’s suggestion of a despicable cover-up by the Vatican, it was hardly surprisingly that the film crew got the cold shoulder.

He might also have upset the churchmen with his ‘editorial licence’ regarding the Rose Line.

Although it is true there is a brass strip running across the floor of the church to a marble obelisk, it is not a meridian line as Mr Brown suggests – that is about a 100 yards or so east of the church.

In fact, in the mid 1870s, France ‘lost’ its meridian line when geographers and scientists across the globe agreed there should be a common zero for longitude and time reckoning.

Greenwich became the Prime Meridian and France agreed to this, on the promise that the British conformed to the metric system. (Well, we are getting there aren’t we?).

Anyway, back to the brass line in Saint-Sulpice. In the south-end window of the church, a system of lenses allows a ray of sunlight to shine onto the line and at the equinox on March 21, the ray touches a floorplate near the altar.

This system was created so all the churches in Paris would celebrate Easter Sunday on the correct day – the first Sunday following the full moon after the spring equinox. That is the official line!

If you visit the church, do not miss Delacroix’s fresco of Saul fighting with the Angel, hidden in a small chapel just as you enter the church. It wasn’t mentioned by Dan Brown, but my Da Vinci Code walking tour guide.

Iris, a 35-year-old American in Paris, has read-up on Dan Brown’s books and uses her authoritative knowledge of Parisian history to fill your head with all sorts of fascinating facts and theories. Mr Brown would have done well to have booked a tour.

The two-hour walk was not all high brow. On the way to the Louvre, looking out for the old brass meridian markers in the pavement (lots are being pinched due Da Vinci Code-itis), Iris allows time for her walkers to stick their noses through the window at the fashion houses and antique shops or stop off to queue at Laudree, the city’s famous patisserie.

In fact, our bunch of tourists walking down the rather prestigious Rue Bonaparte with cream moustaches and custard dripping down their fronts was rather the icing on the cake.

FACTFILE

Where to stay in Paris?

If you can find the money, stay at the Hotel Westminster, a small, but deluxe hotel on the Rue de la Paix, a stone’s throw from Place Vendôme, the Tuileries Gardens and the Louvre. Thomson Cities and Short Breaks offers two nights at the four-star hotel from £369 per person in May. This includes return Eurostar (standard class), breakfast, accommodation and a Paris map/guide book. Alternatively, two nights at the two-star Leonardo De Vinci near Republique costs from £147 per person in May.

For bookings call 0870 606 1476 or visit www.thomsoncities.co.uk

Dan Brown Da Vinci Code walking tours are available through Paris Walks. For details tel: (33) 01 48 09 21 40 or visit www.paris-walks.com

Two-hour guided walks cost from 10-12 euros per person.

Pictures by David P Henry. See more at www.davidphenry.com