Legal action may be taken to save the remains of Carrickmines Castle, in south Co Dublin, from being bulldozed to make way for a major interchange on the South Eastern Motorway.
It is understood that some objectors to the destruction of the complex are considering taking a High Court case to have the medieval site preserved as a national monument.
Archaeologists in Dúchas, the Heritage Service, may be called to give evidence that they had opposed the route chosen by the National Roads Authority because it would traverse the site.
An archaeological dig headed by Dr Mark Clinton, of Valerie Keeley and Associates, which has been going on for two years, is due to end on August 30th though the site will not be fully excavated.
Dr Patrick Wallace, director of the National Museum, said yesterday that while Carrickmines Castle "may not be Wood Quay, it is a site of national importance and should, therefore, be fully recorded".
He said aerial photography should be used extensively to gain an overview of the medieval complex, which was built as one of the main defences of the Pale.
Saying compromise "should be possible", Dr Wallace - who headed the Wood Quay dig in the late 1970s and early 1980s - said the central stone rectangular area should be open to the public.
However, in the case of Carrickmines Castle, the NRA's archaeological adviser, Ms Daire O'Rourke, a former Dublin City archaeologist, said it would be sufficient to record the site as fully as possible.
In response to growing protests over the current motorway plan, the NRA agreed last week to examine whether feeder roads on the Foxrock side of the Carrickmines interchange could be altered. Mr John O'Sullivan, planning officer of An Taisce, said yesterday that it "shouldn't be too difficult" to make the required changes because the Carrickmines stretch was the widest part of the motorway route.
He said the entire South Eastern Motorway - it is the final element of the M50 - was being built in a single-phase contract, "so the contractor can still get on with the rest of the route".
