HARTFORD, Conn. (AP) — The U.S. Navy is testing its capabilities in the Arctic with submarines named after Connecticut and its capital city.

The USS Connecticut and the USS Hartford are participating in Ice Exercise 2018, or ICEX.

The five-week biennial exercise began Wednesday with the arrival of the two fast-attack submarines and a Royal Navy submarine, the HMS Trenchant.

They'll conduct multiple transits through the Arctic Ocean, surface at the North Pole, collect scientific data and train.

The USS Connecticut is from Bangor, Washington. The USS Hartford is from Groton, Connecticut.

The Navy uses the exercise to continue learning the best way to operate in the unique, harsh environment.

A temporary ice camp was established on a sheet of ice. It serves as a command center for submarine operations, including torpedo exercises.