Tulsa.
The halfway point between Tulsa, Oklahoma, and Vicksburg, Mississippi, is Conway, Arkansas, if you're going via Fort Smith, Little Rock, and Pine Bluff.
The city at the geographic halfway point between Sydney, Australia and Chicago, IL is Banana, Kiribati. The closest major city that is roughly halfway is Honolulu, HI.
Philladaliphia
Chicago, Illinois and Atlanta, Georgia are 719 miles apart. A city located halfway between them would be Bonnieville in Kentucky.
Kalamazoo
The exact halfway point is the corner of Ecorse Road and Middlebelt, but that is on a straight line between Wyandotte and Canton.
Atlanta
Elk City, OK
bum
Ragsdale, Arkansas.
North Royalton,OH