An icebreaker is a special-purpose ship or boat designed to move and navigate through ice-covered waters, and provide safe waterways for other boats and ships. Although the term usually refers to ice-breaking ships, it may also refer to smaller vessels, such as the icebreaking boats that were once used on the canals of the United Kingdom.
USCGC Healy (WAGB-20) at right breaks ice around the Russian-flagged tanker Renda, 250 miles (400 km) south of Nome, Alaska.
A 17th-century Russian koch in a museum
City Ice Boat No. 1 at the Delaware River. The paddle steamer was built in 1837.
Yermak is considered the first true modern sea-going icebreaker.
Ice navigation is a specialist area of navigation involving the use of maritime skills to determine and monitor the position of ships in cold waters, where ice is a hazard to the safety of navigation. The presence of sea ice requires a ship to exercise caution, for example by avoiding icebergs, slowly sailing through a lead, or by working with an icebreaker to follow a course through the ice to a destination. Additionally ships must also deal with the extreme cold of the climate in regions such as the poles; this involves removal of ice accumulation from the ship, as well as protecting the crew from the elements while working on the deck. Ships and their crews operating in ice will follow established rules of seamanship, as well as complying with national and international regulations such as the Polar Code.
An example of ice navigation; Russian icebreaker Krasin leading an American supply ship into McMurdo Station, Antarctica
Cargo vessel Claudia navigating in ice, Gulf of Bothnia
Icebreaker Ymer assisting cargovessel Vlieborg