https://www.midwestlsaexpo.com/
“We feel the Midwest LSA Expo is the most convenient and affordable of its type in the country,” says the organizer. “The host City and Airport are located at the crossroads of two major interstates and are 1 hour, 15 minutes by ground from Lambert St. Louis International Airport. Over 1200 hotel rooms and 60 restaurants are within three miles of the event site. Over 50% of the entire U.S. population is within an 8 hour drive from Mt. Vernon!”
Admittance is free, as is parking for ground vehicles and aircraft. A claimed 35 vendors will be exhibiting.