HMS Westminster has returned to Portsmouth after five months safeguarding UK waters.
The Royal Navy frigate was keeping a close eye on submarines on operations as far north as the Arctic circle.
Sailors on board HMS Westminster spent the Christmas period away from their loved ones, after being at sea almost constantly since deploying last summer.
On their return, families gathered at Round Tower to welcome the sailors home from their mission, waving them in as they entered Portsmouth Harbour.
Commander Louise Ray, Commanding Office of HMS Westminster, said coming home reminds crew they "would struggle to do what [they] do without the support" of families and friends.
"Waving to all of those who were on the hot walls and Round Tower today is really important and I thank them, and all of our friends and family who could not make the journey, for the support they show us each and every day when we are deployed."
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HMS Westminster has been at the forefront of the UK's submarine hunting, operating as the Royal Navy's Towed-Array Patrol Ship (TAPS).
The Type-23 frigate has patrolled large areas of the Atlantic using state-of-the-art weapons and sensors to track submarine movements and escort ships through waters close to the UK.
Sailing 24,000 miles, HMS Westminster spent 121 days of the 151-day deployment at sea – stopping in Hamburg in Germany, Trondheim in Norway and Reykjavik in Iceland along the way.
HMS Westminster's operations were diverse, from May Day calls for missing paddle boarders in the Irish Sea to monitoring surfaced Russian submarines.
The frigate had a Merlin helicopter on board, which uses both sonobuoy listening devices dropped into the ocean and sonar lowered – as a helicopter hovers to pinpoint a submarine's presence.
Westminster spent Christmas alongside in Lerwick in the Shetland Islands, which included a bracing open water swim for some hardy sailors.
After New Year's anchored off St Ives, the frigate completed exercises off the South Coast before heading for home.