Spruce Street Harbor Park and Delaware River waterfront are hosting over 500 free events this summer

Lie in a hammock, brunch on the waterfront, listen to Sunday afternoon jazz, take an al fresco Latin dance lesson, and more during this year's Summer on the Waterfront.

May through September, more than 500 free events will unfold along the Delaware River at places including Spruce Street Harbor Park, the Great Plaza at Penn's Landing, Race Street Pier, BlueCross RiverRink Summerfest, and the RiverLink Ferry.

This year's season of events and activities kicks off Friday with the opening of Spruce Street Harbor Park, launching with a three-day festival full of live musical performances, make-and-take activities, food, and more. Blue Cross RiverRink Summerfest will also open up for the weekend with roller skating, mini-golf, the carnival-esque Midway, and food concessions May 11-13 (and May 18-20), prior to its official season opening May 24.

Adding to the fun this weekend, the popular Art Star Craft Bazaar (May 12-13) returns, and free yoga classes on Race Street Pier, a daily offering that began in April, will unfold, too.

Busy this weekend? Have no fear, a litany of other returning popular events and attractions fills the calendar through the end of the warm weather season, including 10 different PECO multicultural festivals (June through September) and weekly movie nights (Thursdays in July and August) at Penn's Landing.

Three free fireworks shows will also spread color over the Delaware River on May 26 as part of Sail Philadelphia, June 30 following a concert by the U.S. Army Band ("Pershing's Own"), and on Labor Day.

A ton of new events are adding to the lineup of free outdoor happenings as well, including jazz nights every third Sunday (3 to 7 p.m.) in Spruce Street Harbor Park and a weekly Sunday farmers market presented by Greensgrow Farms. The waterfront space will also host a Lights + Flights light show every Friday night, enhancing the already majestically illuminated setting with ambient fog and a fully programmed light show, and Sunday brunch opportunities debut this year from the vendors that fill the park. Mimosas on the river are now a fully achievable Philly dream come true.

Penn's Landing will host two new major events this summer, starting with Sail Philadelphia, a five-day maritime festival spread out across Memorial Day weekend, followed by the Pennsylvania Care Health Festival (July 28), featuring free health screenings, yoga, line dancing, and more.

Meanwhile, the new offerings at BlueCross RiverRink Summerfest include a series of Latin Nights, when a free dance class and a night of samba is scheduled to take over the roller-skating rink.

To learn about all of the hundreds of events taking over the waterfront this summer — monthly fishing lessons included — head to delawareriverwaterfront.com.