Minneapolis will never be called the city that never sleeps. But on Saturday, the city's old riverfront factories, bridges, green spaces, art museums and bike trails will become a blank canvas for overnight art.

The second annual Northern Spark festival kicks off at dusk on Saturday and ends at dawn Sunday. More than 200 artists will present works -- many of them interactive -- for audiences willing to be insomniacs for a night.

This year, there's a free mobile app to help you navigate the extravaganza with maps, times and info on artists. Here are eight installations we're hoping to lose sleep over:

Stone Arch Bridge: If this doesn't get your attention, nothing will. Artist Robin Schwartzman has attached giant red illuminated letters to the arches of the famous walking bridge. They spell out "Think and Wonder, Wonder and Think" -- the fest's official theme, courtesy of Dr. Seuss.

Psychedelic Art Parade: A 40-piece marching band clad in LEDs, black-light body paint and glowsticks will lead a procession across the Stone Arch Bridge playing everything from Afrobeat to Eastern European string music. Paradegoers should dress the part (9:15 p.m. at the Mill City Museum, ends 9:45 p.m. at the Soap Factory).

Walker Art Center: Lots to do here, including acoustic music and bedtime stories around an Open Field campfire, with artists making sculptures that will be "liberated by sacrificial burning" (8:58 p.m.-3 a.m.). An all-night video will constantly shuffle 3,000 images, 80 voices and 150 snippets of music. Stories of the paranormal will be told from midnight to 1 a.m., after which 20 performers will whip out their iPads and animate pictures for 20 minutes.

Weisman Art Museum: It's a night of science, nature and art. Lights set out by Bell Museum staff will attract night creatures -- human and insect -- to the Mississippi River bank below the Weisman, where naturalists will explain them (8:58 p.m.-midnight). Owls and other nocturnal birds will arrive from the Raptor Center (10-10:50 p.m.). There will be drawing sessions in the museum till midnight, plus flashlight gallery tours, meditation, storytelling, an all-night "interactive tour of Earth and space" and a concert by Sleeping in the Aviary and Buffalo Moon (2-4:30 a.m.).

"Mom's Cookies": Silent videos of idealized moms stirring up cookies, biscuits and other treats will be projected onto old mill buildings on Main Street near St. Anthony Falls, where package mixes were invented in the 1930s. (8:58 p.m.-5:26 a.m.)

"Warm Up the Greenway": Concerts, improvisatory dance and storytelling, and do-it-yourself posters printed by bike treads will enliven the Midtown Greenway near 28th Street and Chicago Avenue S. (6-9 p.m.).

"In Habit: Living Patterns": This one had us at "a nine-hour overnight outdoor performance at the Central Avenue Bridge underpass." Aniccha Arts will present 16 dance vignettes mixed with electronic music and video (8:58 p.m.-5:26 a.m.).

GLOWaBOUT: One of last year's most popular events, this is neighborhood games meets the Indian Holi Festival. The participatory glow-in-the-dark party will feature a game of Capture the Glowing Orb. Teams will build colorful fortresses and then hit the field outside MCAD dressed in "Glow Bandit" gear -- face paint, powder and anything else that glows (8:58 p.m.-5:26 a.m.).