Great Frederick Fair (Part 2) Issues & Insiders by: Katie Misuraca Posted: Sep 16, 2019 / 11:31 AM EDT / Updated: Sep 16, 2019 / 11:31 AM EDT HAGERSTOWN (WDVM) — For 9 days with 150 vendors, the Frederick Fairgrounds will be packed with thousands of people for the 157th Great Frederick Fair.