Let There Be Music Under the Stars. And Maybe a Sandwich.

A funny thing about classical music in New York City: In the summer, the city gives up its status as a global powerhouse. The Metropolitan Opera House goes dark, Carnegie Hall winnows to a few small events, and the New York Philharmonic performs a handful of concerts in June and then splits for Shanghai and Vail before taking August off completely. Audiences decamp for festivals outside the city, to Bayreuth in Germany or Tanglewood in the Berkshires. Even with the Mostly Mozart Festival in swing at Lincoln Center and Bargemusic floating under the Brooklyn Bridge, the Big Apple finds itself temporarily ceding its programming dominance to the likes of Cooperstown (home of the Glimmerglass Festival) and Katonah in Westchester County (Caramoor, which is now quiet until September).

This is not the New York of October and competitive evening wear. On the other hand, a casual concert alfresco in an urban setting: What fun. Outdoor summer shows in New York go back to at least 1824, when military bands performed in Battery Park at the tip of Manhattan, part of an initiative to civilize the locals.

With the big institutions saving their heavies for fall, things get pretty informal and democratic: free concerts in parks, chamber groups at outdoor weddings, young performers or composers getting their chance in the spotlight. Though you cannot get into the Met Opera House, you can watch past performances on a screen outside. There is even the occasional spectacle, like Saturday’s world premiere of John Luther Adams’ “In the Name of the Earth,” a choral work for nearly 800 professional and amateur singers. (Originally planned to take place in Central Park, just south of Harlem Meer, the 3 p.m. concert was recently moved to the Cathedral of St. John the Divine, at 112th Street and Amsterdam Avenue, because of possible inclement weather). When the sun shines on outdoor events like this one, however, you can bring a picnic and your kids, which is the sort of move they frown upon at the Met. And did we mention free?

And if none of that satisfies your classical music jones, you can always hop a train to Annandale-on-Hudson, where the Bard Music Festival kicks off this weekend with a deep plunge into the music and life of Nikolai Rimsky-Korsakov.

Because after all, in these sweltering days of August, nothing is more New Yorky than getting out of town.