The local mayor had to be bribed with two bottles of grappa. Without those libations, our coach simply wouldn’t have made it down the narrow lane to the great iron gate guarding a grove still sacred to Athena and to Aphrodite. The 450-year-old olive tree belongs to Athena; and the myrtles to Aphrodite, who took refuge in them when emerging from the sea. This sacred grove, on a mountain that erupted from the ocean only 15,000 years ago, won a prize last year for the most beautiful public garden in Italy.

If you take a boat from Naples, and visit La Mortella (The Myrtles) on the island of Ischia, you will learn all this, and more, within the first five minutes inside those iron gates. Lady Walton, aka Susana Valeria Rosa Maria Gil Passo, created the garden while her late husband, Sir William Walton, locked himself away and wrote music.

As storyteller supreme, and indefatigable actress, the 80-year-old widow perches under the olive tree and tells their tale to some 700 visitors a week. First, the arrival on Ischia shortly after the war in William’s Bentley, and their astonishment when the impoverished Ischians were reluctant to give them petrol. Then finding the site for the garden, on the craggy lava-flow of Monte Zaro. “William sent me a shoebox with four sticks of tree-fern in it.” And a Mediterranean garden became a rainforest. “Darwin got it wrong,” says Lady Walton, and lets out torrents of deep-throated laughter. “He said cycads couldn’t be fertilised by insects. Well, once a year, for five hours, the tree’s temperature goes up; it exudes a scent; and the insects are irresistibly attracted to it.”

Basta. The stories are as abundant as the growth of yucca and ginkgo, cycad and camellia. But halfway up the mountainside garden is William’s Rock: the composer’s ashes repose in the apex of a monumental stone pyramid. It keeps guard over house, garden — and the Recital Hall which, since 1990, has celebrated Walton’s memory by providing platforms, courses and masterclasses year round. And a special private music festival every October, solely for the clients of the Kirker Ischia Music Festival at La Mortella.

Engaging young musicians to perform at festivals run by tour operators is a relatively new form of enlightened patronage. And last year the young Doric String Quartet, the pianist Simon Lepper and the tenor Adrian Thompson climbed the magic mountain, together with some 50 holiday-makers, to play and sing Schubert, Webern, Dvorak, Britten — and some Walton — in the glowing acoustic of La Mortella’s rock-hewn Recital Hall. The programmes are as challenging as the climb up the numerous, lava-hewn steps and vertiginous pathways; the performances heady and exhilarating enough to make it all worth the effort. The Kirker travel group, meticulously yet unobtrusively organised, are generally elderly, well-travelled couples, now in search of cultural soulmates; and a smattering of young singles, widows and widowers looking, possibly, for any kind of mate at all.

Outside the environs of the Recital Hall, and the gracious lounges and gardens of the Grand Hotel Excelsior, there are the net-mending sailors of the salty little village of Ischia Ponte. The name isola verde, as Ischia is also known, comes not from the lush vegetation, but from a rare green volcanic tufa, perfect for excavating cool caves to store the island’s wine. Unlike the volcanoes themselves, these troglodyte caverns are still active: they hold the distinctive, tangy wines made from the forastera (white) and guarnaccia (red) grapes, to accompany local specialities such as rabbit cooked in garlic, wine and the most succulent cherry tomatoes you’ve ever tasted (they love volcanic soil), or the sea’s daily feast of fish — bass, bream and gilthead.

The ferry boats draw in to Ischia Porto and to nearby Casamicciola, which was frequented in the 1950s and 1960s by Visconti, Pasolini and W. H. Auden. But their spirits and their haunts are all but gone. The wise and the curious now head out of the touristy port area and take a bus marked CS (circolare sinistra) or CD (circolare destra) on the ring road around the island, and branch off on foot to explore the ancient hill settlements of Fontana and Buonopane on the slopes of the great Monte Epomeo (you can still get to the summit by mule). Or to visit the springs of the thermal baths, such as the Parco Termale Aphrodite-Apollon, bubbling around the perimeter of the island, and drawing the beneficiaries of the German national health service, all earnestly taking their Kurs.

This year, Kirker’s pilgrims will divide their time between Ischia and Sorrento. In the time off from music-making, there are simply so many temptations on the mainland, from Pompeii and Hercula-neum to Naples and the steamy Phlegrean Fields, that the best of both these distant and eternally enchanted worlds is now on offer.

Need to know

Hilary Finch travelled with Kirker Holidays (0870 4211201, www.kirker holidays.com). Its Ischia & Bay of Naples Music Festival package costs from £1,896pp for eight nights’ B&B (two sharing), including return flights from Gatwick to Naples, some evening meals, and all concert tickets. The 2007 festival takes place on October 16-24. Further information on La Mortella is at www.lamortella.it

Summer sounds

Verona Opera, Italy

Verona is the most famous of the open-air festivals for a reason: the atmosphere of its 1,900-year-old amphitheatre filled with 14,000 people. This year, Martin Randall Travel (020-8742 3355, www.martinrandall.com) has availability on August 9-13 (Nabucco, The Barber of Seville, Aida), with half board from £1,490pp with flights.

Glimmerglass, USA

Orpheus is the theme of Glimmerglass 2007, with four productions based on the myth: Monteverdi’s L’Orfeo, the Gluck/Berlioz Orphée et Eurydice, Offenbach’s Orpheus in the Underworld, and Philip Glass’s Orphée running from July 7 to August 28. The scenic backdrop is the Otsego Lake, in the rolling hills of New York State. Tickets from $41 on www.glimmerglass.org or ten-day tours with Travel for the Arts (020-8799 8350, www.travelforthearts.co.uk) from £2,395pp half board.

Aix-en-Provence, France

Wagner’s Ring Cycle is being performed at Aix over four years and this year it’s The Valkyrie. Other operas include Madame Butterfly and The Marriage of Figaro. Tickets to any two operas plus flights and two nights’ B&B costs from £475pp with JMB Travel (01905 422282, www.jmb-travel.co.uk). The festival is June 29-July 22.

Baltic Music Festival

Where better to listen to classical music than at sea? On this new itinerary from Kirker (0870 4211201, www.kirkerholidays.com), you set sail August 28 from Dover for Copenhagen, Oslo and St Petersburg on board The Black Watch, which features onboard concerts as well as music-themed excursions. The 13-night cruise costs from £1,580pp.

Tanglewood, USA

The summer home of the Boston Symphony Orchestra this year features music by Beethoven as well as the operas Don Carlo (July 28) and Così fan tutte (August 11, 13 and 14). Bag a lawn ticket from as little as $18 (www.tanglewood.org) or a sevennight B&B package including flights with Black Tomato (020-7610 9008, www.blacktomato.co.uk) from £1,299pp.

Liszt Festival, Austria

ACE Study Tours music itineraries sell fast, so book now for October 16-22. The seven-day trip to Raiding, where Liszt was born in 1811, includes flights, six concerts, half board, and costs from £1,390pp. Book on 01223 835055, www.studytours.org

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