From the Winwaed Software site :

We also have a series of International Mileage Charts which, when complete, will include every country in the World with more than one city with a population of 1000.

Country tables are organized according to continent:

Africa - http://www.mileage-charts.com/osm/AF/index.shtml
Asia - http://www.mileage-charts.com/osm/AS/index.shtml
Europe - http://www.mileage-charts.com/osm/EU/index.shtml
North America - http://www.mileage-charts.com/osm/NA/index.shtml
Oceania - http://www.mileage-charts.com/osm/OC/index.shtml
South America - http://www.mileage-charts.com/osm/SA/index.shtml

As well as downloadable mileage charts, city listings, maps, and table statistics are provided.

These are computed with OpenStreetMap data and report the shortest route distances in kilometers. Although the OpenStreetMap data is global, coverage varies from area to area. Therefore many of the mileage charts are incomplete. We shall be recomputing the mileage charts on a roughly annual basis, and keeping track of their coverage as the OpenStreetMap database expands.

Henri Willox
http://lac-conakry.blogspot.com/