The owners are brothers David and Donald Wolff, who started the markets in 1991. You can find everything from antiques, collectibles, produce, plants, new items and garage sale items.
There are up to around 700 vendors and thousands of visitors. The market has two locations, in Rosemont and in Palatine. Both are open on Sundays; the one in Palatine is also open on Saturdays.
Wolff's Flea Market
6920 N. Mannheim Road
April through October
Sundays, 6 a.m. to 3 p.m.
1775 N. Rand Road (Just north of Dundee Road)
Saturdays and Sundays
8 a.m. to 4 p.m.