Campaigners against plans to build the M3 motorway alongside the historic Hill of Tara in Co Meath are planning a protest in the area today to mark the longest day of the year.
The summer solstice is being marked at ceremonies on the Hill of Tara and the nearby Newgrange burial mound.
Both sites are believed to have been used by pagan worshippers to celebrate the festival in pre-Christian times.
Campaigners believe the planned M3 will destroy the character of the area, as well as several archaeological sites, and want the Government to designate the area a world heritage site.