Scientists from Devon have made history on what is believed to be the first submersible exploration of the world's largest coldwater reef in the Arctic.
Data and samples from the reef will be studied by the scientists
The 25-mile wide Rost Reef was first discovered in 2002 off the coast of Norway using echo sounding equipment.
Three Plymouth University scientists, taking part in an international expedition, have returned with footage of the habitat.
Pictures show there is an abundance of colourful corals and other marine life.
Scientists believe the reef's marine life has flourished since trawl fishing was banned in the area by the Norwegian Government in 2002.
Jason Hall-Spencer, Marta Soffker and Tina Kerby from the School of Biological Sciences will study data and samples collected on the trip, which they hope will provide clues to the development of the reef from the last glacial period - about 8000 BC - onwards.
Scientists say marine life has flourished since a ban on trawling
An underwater manned submersible called Jago was used on the trip, allowing the Plymouth scientists to descend to a depth of 350m to study the reef in minute detail.
"I have seen reefs off the coast of the British Isles before, but they were nothing like the scale of this one," Mr Hall-Spencer said.
"Very little is known about the unique cold water coral communities that live there, so to get such a close up view was marvellous."