Built in the Total War: Rome II engine, the devs at Creative Assembly have generated a screenshot measuring in at a whopping 30,000 by 9,785 pixels. It's a recreation of the Battle of Teutoburg Forest, which took place in 9 CE between the Germanic alliance and three separate Roman legions.
In AD 9, the Roman general Publius Quinctilius Varus and the 17th, 18th and 19th legions were ambushed in Germania. 15,000 Romans walked into Teutoburg Forest. Not one walked out. Varus' defeat was every bit as stunning as Scipio's victory over Carthage (the subject of our last panorama) and it shook the empire to its very foundations.