Seven people were arrested after hundreds of people attended a rave at Dunsby, near Bourne.
Between 200 and 300 people partied on farmland off Fen Road, starting at around 11pm last night.
Two vehicles were also seized, as were sound systems, and the rave caused noise disruption to nearby residents.
Police say they had "insufficient resources" to shut down the event at its peak but closed down the rave at about 2.30pm today.
Suspects continue to help police with their enquiries.