Endurance was a class 1 icebreaker. Her two Bergen BRG8 diesel engines produced over 8000 shaft horsepower enabling her to travel through ice up to 1 metre (3 ft 3 in) thick at 3 knots (5.6 km/h). Her propulsion system used a computer-controlled variable-pitch propeller and stern and bow thrusters. She carried two ice-modified Lynx helicopters which were instrumental in the making of the BBC Documentary Series Planet Earth in 2006.
Endurance was laid up in Portsmouth from 2009 to 2016, following serious damage caused by flooding following an error during routine maintenance on a sea suction strainer. In October 2013 it was reported that she would be scrapped; in July 2015 the vessel was offered for sale for further use or recycling and left Portsmouth under tow to the Leyal ship recycling Ltd. (LEYAL Gemi Söküm) facility in Turkey on 1 June 2016.
MV Polar Circle was built in Norway in 1990 by Ulstein Hatlo for Rieber Shipping. The Royal Navy chartered her for eight months as HMS Polar Circle from 21 November 1991. She was bought outright and renamed HMS Endurance on 9 October 1992.
Endurance provided a sovereign presence in polar waters, performing hydrographic surveys and supporting the British Antarctic Survey in Antarctica. Her usual deployment saw her in the Southern Ocean and returning to the UK through tropical waters each year. Later, a longer, 18-month deployment was designed to maximise her time available for BAS usage.
In 1997, Endurance made the first visit to Argentina by a Royal Naval vessel since the Falklands War, calling at the capital, Buenos Aires, en route to her Antarctic deployment. That she was seen as a scientific and research vessel rather than a warship facilitated the visit and helped to normalise relations between Argentina and the United Kingdom. She visited the Argentinian port of Mar del Plata in 1998 and returned to Buenos Aires in 2002.