The subject of this painting is an episode from Suetonius's 'Life' of the Emperor Caligula. Confounding a prediction that he would no more become emperor than ride across the Gulf of Baiae with horses, Caligula constructed an artificial floating bridge of boats which he then crossed with a chariot. Following popular accounts, Turner has depicted the bridge as a solid construction. It has, however, like the adjacent palace, fallen into ruin and decay.
The picture was widely admired in 1831. The Times described it as 'one of the most beautiful and magnificent landscapes that ever mind conceived or pencil drew'.