It is important to remember that much of our information about Alexander’s campaigns, successes and policies derives from later historians, whose accounts are often highly idealised and breathless with enthusiasm in the coverage of the young general’s exploits.19 Nevertheless, even if we need to be cautious about the way the collapse of Persia is covered in the sources, the speed with which Alexander kept extending the frontiers further east tells its own story. He was an energetic founder of new cities, usually named after himself, that are now more often known by other names, such as Herat (Alexandria in Aria), Kandahar (Alexandria in Arachosia) and Bagram (Alexandria ad Caucasum). The construction of these staging posts – and the reinforcement of others further north, stretching to the Fergana valley – were new points running along the spine of Asia.