By a nose

If you've stood trackside and felt the thunder of a dozen horses racing past you, then just imagine what it was like in 52BC. Caesar's cavalry numbered some three thousand and Vercingetorix had perhaps twenty thousand horses split between two armies. In the Battle of Dibio, the biggest of the horse battles, around twelve thousand horses took to the field. The sound, the sensation and the dust. I personally conjure up a brown thunderstorm rolling and shouting over the plains now filled by Dijon. But the logistics are just as mind boggling. Feeding and watering tens of thousands of horses everyday, winter or summer? And it wasn't just horses either. Caesar's army also had six thousand mules, the Gauls had at least twice that number of pack animals. Each of these wore cow bells so their attendants could find them in the dark - which is probably the sound missing from movies or documentaries showing ancient armies on the march. Over the trudging hobnailed boots would have been the ever presenting ringing of thousands of bells. And almost certainly, every ancient soldier's memory of sleeping in camp was the tolling of those bells out there, somewhere in the dark, a constant every night he was a soldier.   

Find out if Calvus was a cavalryman