There are multiple ways to determine the halfway point between any two cities. Which method you choose will be based on how you and your other party view the trip between the two places. If you are driving or flying, you could calculate the distance in miles or kilometers and divide by two. You could also calculate the distance in driving or flying time and do the same. If you are attempting to determine a halfway point between Washington, DC and Miami, Florida, for example, you could use the numerical distance between the two, or the time that it would take to drive or fly from either location.
Things You'll Need
 Map
 Calculator

Determine the numerical distance between two cities. Use a site such as TravelMath to determine the flying or driving distances, in miles or kilometers, between two cities. For instance, the flight distance between Washington, DC and Miami is 923 miles or 1,485 kilometers. The driving distance, according to the same site, is 1,058 miles or 1,703 kilometers.

Determine the distance by using the time that it takes to travel between two specific cities. If you know, for example, that it takes around three hours to fly between Washington, DC and Miami, Florida, you can then determine a timebased halfway point. If you know that it takes approximately 17 hours to drive between the two points, you can do the same.

Calculate your halfway point using either numerical distances or travel time between your two cities in question. If you need a halfway point between Washington, DC and Miami, Florida, based on distance, you might find a city that is approximately 500 miles south of the former and north of the latter. This city will likely be in South Carolina. If you need a timebased halfway point, you might choose a city that is approximately eight hours driving distance from both cities or one hour and a half of flying time.

Use a map. The key will show you how much distance on the paper is equal to a certain number of miles. Determine the number of miles between the two cities and divide by two. Then use that same key to find a place that is halfway between the two cities.
Tips & Warnings
 Remember that it takes much more time to drive between two places that simply time on the road. You have to allow for traffic, for a possible overnight stay and for stops for gas or food.
 You may not be able to find direct flights between your starting point and your determined halfway point. If your halfway point is a small town or city, it may require two or three flights to get there, which would add a lot of time and work.
References
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