Carrickmines is an outer suburb of Dublin in Dún Laoghaire–Rathdown, Ireland. The area, still semi-rural, was historically on the border of English control and featured a defensive construction, Carrickmines Castle, which became the subject of national controversy during the building of a late stage of Dublin's M50 orbital motorway.
During the construction of the M50 motorway Carrickmines gained national notoriety when anti-roads protesters calling themselves The Carrickminders set up camp in the area and delayed the completion of the M50 for 2 years with legal challenges being taken by Vincent Salafia. The objectors claimed that the underground remains of Carrickmines Castle, an Anglo-Norman fort built in the 12th Century on the edge of the Pale, was of great national importance. Today, much of the uncovered remains are preserved in tunnels and other structures scattered around the interchange. Dún Laoghaire–Rathdown County Council claimed the action greatly increased the cost of the project, which was eventually completed in August 2005.