The Royal Navy's fourth Astute-class submarine HMS Audacious arrived at her new home at HM Naval Base Clyde in Faslane.
Sailing from Barrow-in-Furness, the boat was welcomed in Scotland by members of the Submarine Flotilla.
Audacious joins sister-submarines HMS Astute, HMS Ambush and HMS Artful at Faslane.
Commodore Jim Perks Head of the Submarine Service said it was "with great excitement" that Audacious arrived in Clyde.
"HMS Audacious represents an ever-improving example of the world-leading Astute-class submarine," he added.
"She is right at the cutting-edge of technology, built here in the UK by our own people.
"She will provide the country with remarkable security at sea to protect our nation’s interests."
The Royal Navy says HMS Audacious, which was launched in April 2017, is one of the most sophisticated ever constructed for the service, and is equipped with both Tomahawk Land Attack Cruise Missiles and Spearfish heavyweight torpedoes.
The submarine is also able to make its own oxygen and drinking water, having been and designed for long haul trips while submerged under the water.
In the future, she will be joined in the Astute-class by HMS Anson, HMS Agamemnon and HMS Agincourt, which are currently being constructed in Barrow.
HMS Audacious will now undergo onshore training before continuing on to further sea trials.
Cover image: Royal Navy.