By this time next year it's a good bet we will have heard every morsel Mozart ever wrote several times over. But the Buxton festival has got in early with its contribution to the impending 250th anniversary with what is almost certainly the first ever staging in Britain of Ascanio in Alba, the esta teatrale that the 15-year-old Mozart composed on a visit to Milan in 1771. He had just had a big hit there with Mitridate, and Ascanio in Alba was commissioned as part of the celebrations for a royal wedding. The text, based on an episode in the Aeneid, is a flimsy allegory in which the goddess Venus tests the love and resolve of her son Ascanio for his bride-to-be Silvia, before allowing them to marry and rule over the new city of Alba.

It's not a great plot, and clearly didn't fire the teenage Mozart's imagination very consistently. His score, which is tactfully cut in Harry Christopher's Buxton performance, has a few striking moments - anticipating the later operas right up to The Magic Flute - and just a couple when the music seems to seek out real emotional depths. There are very few ensembles, and the rest is a sequence of routine da capo arias, separated by acres of recitative. Of course it's all wonderfully assured and scored, but might have been designed so as not to distract the wedding guests from their carousing.

The production by Stephen Lawless updates most of the action to a modern wedding party, with Venus (Lynda Russell) as a champagne-swilling matriarch, and Ascanio (counter tenor William Purefoy, impressive in a demanding role) as an adolescent schoolboy, still finding his way in the world, while Silvia (the excellent Gillian Keith) suffers her tribulations in an Arcadian landscape straight out of Gainsborough. It's done with the right light touch, if not always quite enough humour; play Ascanio in Alba really straight and it would become a very long evening indeed.

· Performances on Friday, July 18 and July 24. Box office: 0845 127 2190.