Avon and Somerset Police are appealing for information to help find the people responsible for vandalising vehicles and offices at the Hinton garage compound on the Lower Bristol Road.
Every vehicle and building on the site was attacked on Sunday afternoon, 20th July.
Windscreens and windows of at least a dozen trucks and cars were smashed and some were sprayed with offensive graffiti.
The vandals also forced their way into offices and smashed every pane of glass and every fluorescent lighting tube.
Police would like to hear from anyone who may have seen a group of people in the compound or walking by the river nearby at around 1pm-2.30pm.
Anyone with information is asked to call Bath police on 101 quoting crime reference number 73937/14.