Underground Arts, 1200 Callowhill St.
8 p.m. Friday, $16.
Chicago's post-rock pioneers Tortoise have been brewing a potent mix of electronica, jazz, and minimalism for nearly three decades. Touring behind their first album in seven years, The Catastrophist (which features a warped cover of David Essex's 1973 hit "Rock On"), they headline a four-band bill at Underground Arts.
Arthur Ross Gallery in the University of Pennsylvania's Fisher Fine Arts Library Building, 220 S. 34th St.
10 a.m. to 5 p.m. Friday, noon to 5 p.m. Saturday and Sunday. Admission is free.
Since 1978, Iranian photographer Abbas has been documenting regional struggle and crisis. The exhibit Children of Abraham collects 66 of his images taken for Magnum looking at the way faith intersects with conflict.
Christ Church Neighborhood House, 20 N. American St.
8 p.m. Friday, 3 and 8 p.m. Saturday. Tickets: $15 to $20.
The dynamic, all-female, aerial-dance troupe Tangle Movement Arts will perform its distinctive mix of circus arts, trapeze arts, acrobatics, dance, theater, and spoken word.
Greater Philadelphia Expo Center at Oaks, 100 Station Ave., Oaks.
10 a.m. to 6 p.m. Friday and Saturday, 10 a.m. to 5 p.m. Sunday. Tickets: $10 (good all three days); ages under 12 free.
More than 300 American artisans present their handmade wares, including pottery, sculpture, glass, jewelry, fashion, and furniture at the Sugarloaf Crafts Festival.
Aulenbach Parish House, 29 W. Tulpehocken St.
2 p.m., Saturday Admission is free; reservations required by calling 215-438-1861