Caltrop

• A Caltrop, also known as a ‘Tribulus’ or ‘Murex Ferreus’, was a Roman and Greek anti-horse device.

Description

• The Caltrop consisted of an iron device with four spikes in the shape of a tetrahedron, so that whichever way it was positioned, one spike always ended facing upwards.
• It was used to destroy enemy horses drawing chariots, cavalry and elephants.

Vegetius

• Vegetius states in ‘De Re Militari’ that Caltrops were used to stop the massed chariot attacks of Antiochus and Mithridates.
• As soon as the horses ran over them they became useless.

Use in Battles

• In 331 BCE, the earliest recorded use by Alexander the Great at the Battle of Gaugamela against the Persian Chariots. As described by Quintus Curtius (IV.13.36).
• In 53 BCE, by Crassus at the Battle of Carrhae against the Parthians.
• In 52 BCE, by Julius Caesar at the Battle of Alesia against the Gauls.