OTTAWA -- A quick look at the history of the four warships that are being decommissioned by the Royal Canadian Navy:

HMCS Iroquois and HMCS Algonquin

Class: Air defence destroyers that serve as command and control platform.

History: Built in the early 1970s in Sorel, Que., but refitted with improved propulsion, anti-air weapons and communications systems in early 1990s.

Firepower: Weapons include a 76-mm super rapid gun, a 20-mm six-barrelled Vulcan Phalanx Gatling gun that can fire up to 3,500 rounds per minute; along with anti-submarine warfare weapons including two torpedo-carrying helicopters and ship-launched torpedoes.

Missions: In peacetime, used in search and rescue, fisheries and sovereignty patrols.

Specifications: Weighs 5,100 tonnes and is 129.8 metres in length.

HMCS Iroquois highlights: Its home port is Halifax. It was involved in the rescue of crew aboard a Panamanian fishing boat that was in danger of capsizing off Newfoundland in 1983; rescued 13 survivors and recovered six bodies from a bulk carrier that went down off Bermuda in 2000; participated in a 193-day deployment as part of the U.S.-led coalition against terrorism in the Arabian Sea in 2001; a Sea King crashed on her deck in 2003, no one was injured.

HMCS Iroquois Canadian warship

HMCS Algonquin highlights: Based in Esquimalt, B.C. It has taken part in more than 20 multinational exercises; began refit in 1987, but labour problems delayed completion until 1991; transferred to the West Coast in 1994; in 1997, it began a 12-month, $15-million refit that cost almost $25 million; participated in coalition against terrorism in Arabian Sea in 2002; collided with HMCS Protecteur while en route to Hawaii in August, leaving it damaged.

HMCS Protecteur and HMCS Preserver:

Class: Auxiliary oil replenishment ships resupply task groups at sea with food, munitions, fuel, spare parts and other supplies.

History: Built in Saint John, N.B., and commissioned in 1969.

Capabilities: They can carry 14,590 tonnes of fuel, 400 tonnes of aviation fuel, 1,000 tonnes of dry cargo and 1,250 tonnes of ammunition. They can transfer stores to other ships through hook-up lines and refuelling hoses.

HMCS Protecteur Highlights: Its home port is Esquimalt, B.C. It participated in economic embargo of Iraq in 1990; in 1992 helped people affected by hurricane Andrew in Florida; underwent a refit from 1992 to 1995; part of multinational forces responding to the crisis in East Timor in 1999; participated in Op Apollo in the Arabian Sea in 2002; suffered a major engine room fire last February that caused her to be towed into Pearl Harbor; collided with HMCS Algonquin while en route to Hawaii in August, leaving it damaged.

HMCS Protecteur towed

HMCS Preserver Highlights: Based in Halifax. It acted as a supply ship in 1974 for Canadian troops in Cyprus as part of a UN peacekeeping force; served in UN sanctions against Haiti; joined the multinational force carrying out sanctions against the former Yugoslavia in 1994; participated in the recovery efforts after the Swissair crash off Nova Scotia in 1998; supported counterterrorism efforts in the Arabian Sea after the Sept. 11 attacks in the U.S.; suffered a jetty collision in Halifax in 2011.

HMCS Preserver, a Royal Canadian Navy supply ship