Join The Chisholm on the third Thursday of May, June, July, and August for a free Summer Sounds Concert series. Plan to come early and enjoy dinner from a featured food truck beginning at 6 p.m., spread out your favorite blanket, set up a comfy lawn chair, and enjoy live music from 7 to 8:30 p.m. at Horizon Hill, the home of territorial governor A. J. Seay. The family-friendly event is free. For more information, contact the museum at 405-375-5176.…