According to Suetonius and Dio, he summoned his legions to the shore, arranged them in battle formation, and ordered them to prepare for an assault on the sea.

Trumpets sounded, arms were raised, and the soldiers awaited further instructions as if facing a real enemy.

Then, with no warning, Caligula dismissed the battle and declared victory. Ancient authors later interpreted this as a symbolic triumph over the god Neptune. Next, he instructed the troops to collect seashells along the beach and store them as trophies of the campaign.

According to these accounts, the shells were boxed and carried back to Rome as “spoils” of the conquest.