THIS WEEKEND

Black on blue

A major exhibit of African-American maritime history opens today at the Independence Seaport Museum. Naval heroes, inventors, explorers and abolitionists are represented in this traveling exhibit called "Black Hands, Blue Seas," which originated at the Mystic (Conn.) Seaport Museum. Abolitionist Frederick Douglass, who escaped slavery disguised as a sailor, and Matthew Henson, who trekked to the North Pole with Robert E. Peary in 1909, are among the figures in this exhibit.

Independence Seaport Museum, Columbus Boulevard and Walnut Street, 10 a.m.-5 p.m. daily, $10, $7 children and seniors, $5 military, free on Sundays from 10 a.m.-noon, 215-413-8627.

Trippin' at the Mall

Journeys Backyard Barbecue, an alternative-sports and music festival, sets up camp at the King of Prussia Mall, the final stop on a five-city national tour. Watch skateboard and motocross demos by extreme athletes, listen to alternative music (Even the Resolution, All Time Low, Jealousy Curve and others) all day long, and play interactive games. Philly boasts an appearance by X Games Silver Medalist Greg Lutzka and skateboard superstar Chris Haslam.

King of Prussia Mall, venue opens at noon today, free, www.journeysbbq.com.

Mad about you

"Daily Show" angry man Lewis Black is a graduate of the Yale School of Drama and a best-selling author, whom Jon Stewart calls "the only person I know who can actually yell in print form." He comes to the Free Library to yell about his new book "Me of Little Faith," in which he takes on religion.

Free Library of Philadelphia, 1901 Vine St., 6 p.m. tomorrow, $6-$12, 800-595-4TIX, www.freelibrary.org.

Out and about

The 20th LGBT Pride Parade kicks off at noon at 13th and Locust streets, traveling east on Market Street past a reviewing stand at Independence Hall, before marching to the Great Plaza at Penn's Landing. That's where the Philly Pride festival takes place, with entertainment, food and drink plus more than 120 organizations and merchants participating.

Great Plaza at Penn's Landing, Columbus Boulevard from Market to Walnut streets, noon-6 p.m. tomorrow, $10, www.phillypride.org.