OVERSEAS EVENTS Here's a selection of Europe's festivals:

* Austria

Salzburg Festival, Salzburg

At this year's musical extravaganza, the London Symphony, the Vienna Philharmonic, the Cleveland Orchestra, and others will perform works by Debussy, Berg, and Mahler. Dates: July 25 to Aug. 31. Box office: Ticket Office of the Salzburg Festival, A-5010 Salzburg, Postfach 140, Austria.r France

Aix-en-Provence Festival, Aix-en-Provence

Mozart's ``The Magic Flute'' will be the featured opera in the 1,200-seat open-air theater of the 18th-century Archbishop's Palace. Dates: July 15-30. Box office: Festival d'Aix-en-Provence, Palais de l'Ancien Archeveche, 13100 Aix-en-Provence, France. * Germany

Munich Opera Festival,

Munich

The renovated National Theater and the Altes Residenztheater are where six new productions, including a world premiere, Eckeheard Mayer's ``Sansibar,'' will be performed. Dates: July 6 to 31. Box office: Festspielkasse der Bayerischen Staatsoper, 11 Maximilianstrasse, D-80539 Munich, Germany.r Italy

Festival of Two Worlds, Spoleto

Dance, concerts, and opera are the main features. Dates: June 22 to July 10. Box office: Festival Dei Due Mondi, Teatro Nuovo, I-06049 Spoleto, Italy, or 18 Via Beccaria, I-00196 Rome, Italy. * The Netherlands

Holland Festival,

Amsterdam

Highlights include rarely performed works such as Chausson's ``Le roi Arthus'' and ``Maschinist Hopkins'' by Max Brand. Dates: June 1 to 30. Box office: Holland Festival, Kleine-Gartmanplantsoen 21, NL-1017 RP Amsterdam, The Netherlands.r Scotland

Edinburgh Festival, Edinburgh

Theater and music abound, with the concert roster featuring tenor Jerry Hadley, violinist Midori, and soprano Carol Vaness. Dates: Aug. 14 to Sept. 3. Box office: 21 Market Street, Edinburgh EH1 1BW, Scotland.