Tourism and local authority chiefs yesterday criticised the vandalism carried out at historic Lissadell House.
Sligo County Council chairman Patsy Barry and North West Tourism chief executive Paul McLoone said the attack was an "outrage".
Mr McLoone said the "opportunistic" attack could undo much good work in promoting the region. He said a US crew last week completed filming in Lissadell for a 10-minute slot on Sligo, to be screened on 10 US TV networks in the new year.
"They told me they got magnificent shots in Lissadell and the programme would showcase Sligo very well. I hope and pray they haven't heard about this outrage," Mr McLoone said.
Mr Barry, who lives a few miles from Lissadell, the ancestral home of republican hero Countess Markievicz, said the new owners had gained much valuable publicity for Sligo with their improvements to the estate and their plans for it as a tourist attraction.
Gates and barriers were cut from their supports and dumped in woodland and a river in the weekend attack. Damage was estimated at €5,000. The vandals daubed messages claiming automatic rights of access for the public through the estate for the last 100 years.
The attack was the latest episode in a two-year row over access since the new owners, Eddie Walsh and his wife Constance Cassidy, took possession.