E.g., depart Chicago from O'Hare to Denver, then return to Chicago from Denver, arriving at Midway? Choose Multi-city, and specify specific airport codes at th

E.g., depart Chicago from O'Hare to Denver, then return to Chicago from Denver, arriving at Midway? Choose Multi-city, and specify specific airport codes at the originating / terminating metro area. E.g., American 1017 ORD to DEN on 7 Jan and Frontier 534 DEN to MDW on 14 Jan for $211.