Booterstown Salt Marsh - Eleven acres (4 hectares) of land enclosed by railway, main road and culvert. Forms an entire self sufficient ecological habitat.
Martello Towers - Coastal fortifications from the Napoleonic era. The British Crown erected a network of defensive towers around the coast at locations most vulnerable to attack. 50 Towers are known to have been built in Ireland, 9 of these are in the greater Dun Laoghaire area.
East Pier Lighthouse - Granite lighthouse completed in 1842.
Royal Irish Yacht Club - Erected in the 1850's. One of the world's first purpose-built yacht clubs.
The Forty Foot - Bathing place. Constructed by Kingstown Town Commissioners in 1863.
Monkstown Castle - Built in the 14th or 15th centuries by the Cistercian monks of the Abbey of St. Mary to protect the monks and local inhabitants from the attacks of the O'Tooles and O'Byrnes.
Bullock Castle - 13th century castle built by the Cistercian monks of the Abbey of St. Mary in Dublin to protect the harbour for local fishermen. The stone carving about twenty feet (6m) high on archway under the western tower is known as 'The Dane's Head'. Located at Bullock Harbour.
Dalkey Castles - Two 15th century castles which, with Bullock castle, are all that remains of the seven castles associated with Dalkey town.(i) Archbold's Castle was formerly a fortified warehouse, of which two storeys remain.(ii) Goat Castle adjoins the old graveyard and ruined church dedicated to St. Begnet. Name comes from the goat on the coat of arms of the Cheevers family, former owners of the castle, which is now Dalkey Town Hall. The castles stand opposite each other in Castle Street, Dalkey.
Colimore Harbour (An Caladh Mor) - Ancient harbour. Most important Dublin port until the late 16th century.
Kilgobbin Castle - Once a substantial 15th century Pale castle, this is now an imposing ruin.
Sli Cualann - Rock Road forms part of the pre-Christian Sli Cualann which connected Tara with South Dublin and East Wicklow.
Ballycorus Leadmines & Chimney - Built on the site of Carrickgollogan in the late 1860's of local granite and brick. Traces of the leadworks are still visible.
Leopardstown Racecourse - Opened in the 1880's on a site vacated by Benedictine monks in favour of Buckfast Abbey.
Dundrum Castle - Part of fortification built by Anglo-Normans to protect Dublin City from the O'Byrnes and the O'Tooles. Among the owners was the Fitzwiliiam family whose name is very much in evidence in Dublin. They were related to the Pembrokes to whom estate ground rent is still paid in sections of Dundrum today.
Packhorse Bridge - 17th century double-arched stone bridge originally part of the packhorse commercial route between Wicklow and Dublin. Now part of the pedestrian system in the Dodder Valley Park.
Churchtown Bottle Tower - A folly erected during the bad winter of 1741/42 as relief work for the poor. The Tower and its smaller colleague are similar in design to the "Wonderful Barn" near Leixlip, built in 1743 by the Connolly's of Castletown.
Fernhill Gardens - 40 acres (16 hectares) of gardens attached to Fernhill House contains thousands of plants and trees. Some specimens date from the early 19th century.
Marlay Park - 214 acre (87 hectare) park which originally formed part of the grounds of Marlay House. Acquired by Dublin County Council as a public park in the 1970's. Now administered by Dun Laoghaire-Rathdown County Council.
Milltown Viaduct - Spectacular nine arched limestone bridge over the river Dodder. Formed part of the Bray-Harcourt Street Railway Line which closed in 1958.
Manor Hill Laundry & Waterfall - Originally the site of a 15th century corn mill. Continued life as a laundry until 1940's. Site is now a bowling alley.