Tomorrow, June 21, is the summer solstice, the longest day of the year, and there are definitely ways to mark the occasion. The biggest event is tomorrow's annual Solstice in Times Square, where people flock to practice yoga in the middle of the city. Pre-registration for the 1,200 spots has closed, but you can sign up for the waiting list.

You can also admire the yogis in action throughout the day (there are five classes)—besides seeing them in person, you can watch a webcast—and perhaps be inspired to sign up for a yoga class yourself. Plus there are fashion shows from Athleta. (Friday, June 21, starting at 7:25 a.m.; Broadway between 43rd and 48th Streets in Times square)

The North Brooklyn Boat Club, a volunteer group advocating for more human-powered boating around around Greenpoint and Williamsburg, is having its second annual Summer Solstice Party, also tomorrow. The all-ages show has the Radicators, Daredevils of the Red Circle, Fetzig, Sasha Dobson, and Taluna, plus they'll be grilling food. (Friday, June 21, 6:30 p.m.-midnight; $5 cover, Broadway Stages Boatyard, 437 McGuinness Boulevard at Ash Street in Brooklyn)

A stunning concert will be held very early on Saturday at The Cathedral Church of St. John the Divine: Paul Winter is presenting his 18th annual Summer Solstice Concert. Here's how St. John the Divine describes it, "Imagine yourself inside the world’s largest Gothic Cathedral in the predawn darkness as the canyon-esque space resounds with earth music." Winter himself says, "We begin playing in total darkness at 4:30 a.m. within the awesome space and acoustics of the Cathedral of St. John the Divine. We embark on a continuous two-hour musical journey, with players stationed in distant corners or moving among the audience. Somewhere near the halfway point, listeners gradually realize that the Cathedral’s great stained-glass windows are beginning to illuminate. The light joins the sound to carry us into the first dawning of summer." (Saturday, June 22, 4:30 a.m.; $35, 1047 Amsterdam Avenue in Manhattan)

The Queens Botanical Garden also has solstice fun planned on Sunday: There's a bird walk and nature walk, as well as old fashioned children's games and face-painting. And you can also explore the garden's 39 acres! (Sunday, June 23, 11 a.m.-4 p.m.: Free with $4 admission fee; 43-50 Main Street, Flushing, Queens)