Free outdoor music

In the summer, music spills out into the streets and courtyards and parks, and it won't cost you a thing.

Celebrate the first day of summer with this international festival, featuring more than 100 local bands in 19 locations around Harvard Square. You'll hear a little bit of everything: rock, reggae, Latin, DJs. 1 p.m. Harvard Square, Cambridge. After party 10 p.m. Winthrop Park. Information and schedule available at booths on Brattle and Palmer streets. makemusic cambridge.com

The Boston Harbor Hotel series on Rowes Wharf features Summer Soul on Tuesdays, starting June 24, featuring R&B and Motown acts. Wednesday's Summer Swing, starting June 25, features the White Heat Orchestra playing big band jazz for dancing under the stars. Thursday's Blues Barge kicks off June 26 with blues harpist James Montgomery. Runs through the end of August. 6 p.m. Boston Harbor Hotel, Rowes Wharf, Boston. 617-439-3995. bhh.com

This marks the 10th year for these Fenway jazz concerts curated by the Berklee College of Music. Berklee teacher, jazz pianist, and vocalist Carolyn Wilkins gets to let loose when she launches the series July 9. Folding chairs, blankets, and picnic dinners encouraged. Runs through July. 6:30 p.m. Mothers Rest, corner of Boylston Street and The Fenway, Boston. 617-747-2447. berklee.edu/events

The Harvard Square folk mecca hosts a midday singer-songwriter and folk-oriented series once a week in Kendall Square. Local folk-blues singer and guitarist Rose Polenzani performs July 9, and bluegrass artist Jake Armerding picks and sings July 30. Runs through August. 12:30 p.m. Two Cambridge Center Courtyard, Broadway and Third streets, Kendall Square, Cambridge. 617-577-7354.

Kendall Square is also home to Berklee's Jazz Revelation Records series of jazz, Latin, R&B, and funk. Serbian singer Jelena Bracika performs July 3. Runs through Oct. 2. Noon-2 p.m. 300 Athenaeum St., Kendall Square, Cambridge. 617-577-7354. berklee.edu/events

The Berklee Latin Jazz All-Stars - six top scholarship students from Puerto Rico, Israel, and the United States - (performing July 17) are among the artists performing at La Casa de La Cultura's Latin music series, held July 10-31 at O'Day Park in the South End. 7-9 p.m. 85 West Newton St., Boston. 617-927-1739. claboston.org

For weekly concerts on its outdoor plaza, the ICA partners with, you guessed it, Berklee. (What are you going to do: The school has a lot of musicians hanging around.) Scottish harpist Maeve Gilchrist gets things going on June 19. Series runs through Sept. 11. 6- 8:30 p.m. Institute of Contemporary Art, 100 Northern Ave., Boston. 617-478-3100. ica.org, berklee.edu/events

For pop and emo fans, this year's shows at the Prudential Center garden are a lunchtime must. The series begins June 26 with pop singer-songwriter Tristan Prettyman. On July 10, it's rockers the Spill Canvas, hot off a sold-out show at the Middle East in early June. Shows run through August. 12:30 p.m. Prudential Center South Garden, 800 Boylston St., Boston. mix985.com

Boston's grandest free outdoor concert is the Boston Pops' Fourth of July extravaganza. It's part of a summerlong concert spree that includes disco boogie from KC and the Sunshine Band Aug. 16 and the Landmark Orchestra's performance of Verdi's "Requiem," which closes the series Sept 10. 7 p.m. Hatch Shell, Memorial Drive, Boston. mass.gov/dcr/hatch_events.htm