I have found some topics here which cast a doubt on Alexander's greatness. Some people compare Ceasar with him, while few others tried to say Genghis Khan is greatest. As those posts are years old, I am creating a new thread on this topic.
To support my opinion that Alexander is greatest commander, I would like to attach 2 tour maps. One is of Alexander and another of Julius Caesar. If anyone look at the maps, he/she can easily understand the greatness of Alexander.
Keep in mind, Alexander the Great have reached various parts of the world within a short life-span of 33 years. If he had managed a 60 year life, wouldn't he conquered all parts of the world?
Tour map credit: Wikitour