What is the halfway point between Cleveland OH and Tulsa OK?

The halfway point between Cleveland Ohio and Tulsa, Oklahoma, going by Interstate highways, is St. Louis, Missouri. It takes approximately 11 hours to drive from Cleveland Ohio to St. Louis, Missouri, and another 11 hours from St. Louis, Missouri to Tulsa, Oklahoma. Of course, 11 hours means straight through driving and depends on good weather and traffic. Most people take breaks every three hours, for anywhere from 15 minutes to an hour delay each time.