No-cost entertainment abounds in Boston during the warmer months

Harvard Art Museums: As of late June, the venerable Cambridge-based university has opened its esteemed collection of international art treasures to the general public for no admission. Thanks in part to the generosity of a recent donation, anyone can now visit during open hours Tuesday through Sunday to see thousands of priceless works from all over the world for free, in perpetuity.

Boston Harborfest: As the critical focal point that sparked American freedom, the Hub goes all-out for the Fourth of July holiday, especially with this free, multi-day celebration of revolutionary spirit. From June 30–July 4, enjoy such highlights as a kickoff ceremony (June 30 from 11:30 a.m.–1 p.m.) and music and live performances (June 30–July 3 from noon–8 p.m.) at Downtown Crossing, a fireworks display over Boston Harbor (July 1 at 9:15 p.m.), the annual soup-sampling extravaganza known as Chowderfest (July 3 at 2 p.m.) and a parade from City Hall to the Old State House, where the yearly reading of the Declaration of Independence takes place (July 4 at 9 a.m.).

Boston Pops Fireworks Spectacular (pictured): The beloved orchestra performs its annual program of patriotic favorites on the Charles River Esplanade’s Hatch Memorial Shell on July 4 from 8–11 p.m. with special guests En Vogue, among others. All this culminates in the familiar finale of Tchaikovsky’s 1812 Overture, followed by one of the best pyrotechnic displays anywhere.

Science on the Screen: The Rose Kennedy Greenway hosts a wide array of free occurrences throughout the summer, including this outdoor version of the film series sponsored by Brookline’s Coolidge Corner Theatre, which continues July 12 with The Lost World: Jurassic Park and August 16 with It Came from Outer Space. As with the indoor iteration, this open-air screening at Wharf District Park is preceded by a talk by an expert who reveals real-life facts relating to each movie.

The Jim Irsay Collection: The Indianapolis Colts owner’s famed collection of guitars, musical instruments and more comes to the TD Garden July 15 accompanied by a free concert that features such special guests as REO Speedwagon frontman Kevin Cronin, country music superstar Vince Gill, R.E.M. guitarist Mike Mills, Boston legend and J. Geils Band singer Peter Wolf, and blues rocker Kenny Wayne Shepherd. Guests must register in advance for entry, and are encouraged to donate to mental health awareness charity Kicking The Stigma.