For all cities with a population greater than one million, Udon Thani is closest to Bangkok and farthest from Lima. The closest foreign city is Bat Dambang and the farthest domestic city is Bangkok. See below for the top 5 closest and farthest cities (domestically, internationally and by continent) and to see which cities, if any, Udon Thani is the closest and farthest to. Filter to include all cities over 100k, 500k or 1 million in population.