Earth at the Antonine Wall, near one-time Roman fort Rough Castle in Bonnybridge, was cut and disturbed between Monday, March 1 and Monday, March 8.
Damaging a World Heritage Site is a criminal offence.
Larbert-based police are appealing for information in a bid to trace those responsible.
Anyone who has information relating to this inquiry is asked to call 101.
Quote incident number 2595 of March 15.