In his grand plan for the amazingly engineered gardens at the palace of Versailles . . . which cost untold amounts of money and the lives of countless workers, who were killed by the marsh gas that escaped during massive excavations for artificial lakes and other "water features" . . . Louis included an enormous outdoor chessboard, on which he played the game by moving real people, dressed as chess pieces, around the squares.

And the French, who are masters at making great parks for the people and at planting more and more street trees for their wellbeing and happiness, are still having fun with their gardens, most notably this year at the ground-breaking and influential Chaumont Gardens Festival, where the design theme for the 30 new gardens now on show (until 15 October) is 'Play in the Garden', aimed at adults as well as children.

"Our aim for this 15th year of the festival, " they say, "is to play and play and have fun and thrills", not only with the new gardens but with the intriguing permanent ones, left there to evolve over the years of the festival, including the mysterious fog valley and what the French call in translation "the path of wild irons", which is all about rusted metal constructions leading through a wooded wilderness, an idea that has been imitated by garden designers ever since it was unveiled.

In their pursuit of fun and games, the 30 designers at what is really an international gardens laboratory have come up with an eclectic but inspirational array of themes and garden games, some fully interactive. They include a modern take on Louis XIV's chessboard (and Alice in Wonderland) that uses planted pots on castors instead of real people as pawns.

There are gardens that are whole gambling games, word mazes, games with mirrors and light, water games, children's games and "naughty games" (though something could have been lost in translation on that one).

There is an awful lot going on and much of it is strongly architectural, as is usual at Chaumont, where leading visual artists and architects often take a stand or work closely with landscape and garden designers.

There will be unusual and no doubt inspiring tree houses, miniature croquet lawns and golfing greens you could copy at home. There will be labyrinths and mazes to get lost in (or for safely losing children in), music gardens and the thrill, as the French so quaintly put it, of "hiding his loves in a cave".

Then there are the plants, in case we forget this is a garden festival, and they will be included in the games along with being being the main element of the gardens, with a series of botanical treasure hunts planned.

Part of the charm of Chaumont is not just the new and permanent gardens but the fairytale chateau (which you can visit for an extra fee), its extensive grounds, the great restaurants and the food and wine stalls selling fresh walnuts, cheeses and local wines.

Chaumont, on the Loire River, is situated between Tours and Blois. Frequent trains to the local station take two hours from Paris or Nantes and the journey also takes about two hours by car from Poitiers as well as Paris.

It is also, they tell us, just in case we want to play on the way as well, three days by horse from Paris and two days by tandem from that beautiful city.

Chaumont is open every day until twilight from now until 15 October and is well worth a visit.

For more information, phone 0033 254 209922 or log on to www. chaumont-jardin. com

DIARY 17 May: The Moore Lecture: 'Oxford Botanic Gardens . . . The First 385 Years' by Timothy Walker at the Glasnevin Botanic Gardens, Dublin 9, at 8pm.

23-27 May: The Chelsea Flower Show, London (booking www. rhs. org. uk). Elma Fenton from Kildare, who won silver-gilt for her "rst show garden at Chelsea last year featuring a natural swimming pool complete with swimmer, is making a garden for Hampton Conservatories this time around. Another Irish element will be Kilmurry Nurseries of Gorey's first stand in the Great Pavilion.