St. Charles Flea at the St. Charles City Hall Parking Garage. St. Charles Flea is a high end flea market occurring (rain or shine!) on the 2nd Saturday of the month, July-September, at the parking garage of the St. Charles City Hall in Historic St. Charles. It will feature furniture, clothing, collectible, antiques, jewelry, art, and crafts from local artisans and designers. Plus, food trucks and live music! See website or Facebook page for more info.