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.CharacterTraditionally a rural area, and today a semi-rural suburban region, Carrickmines is now divided northeast/southwest by the M50 motorway, with, to the northeast, more established residential areas, and to the southwest, notably along Glenamuck Road, new retail parks, office buildings, and housing schemes including many apartments.GeographyCarrickmines developed as a key settlement in the more than 6 km long valley of the same name, which contains the modest Carrickmines River and its tributaries. The Ballyogan, Glenamuck and Golf Streams all merge in the vicinity. Downstream at Brennanstown the river merges with St. Bride's Stream, from Foxrock, to form the Loughlinstown River, which in turn meets the Bride's Glen Stream to form the Shanganagh River, which reaches the sea at Killiney Strand.Leopardstown lies to the northwest, Foxrock to the north, Cabinteely to the northeast and Brennanstown to the east, Ballyogan to the west, Glenamuck to the south, and Laughanstown to the southeast.HistoryThe CarrickmindersDuring 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.