I just felt like I was holding my breath for six hours...’

When Dr Cath Robinson returned from holiday she was greeted by a mound of post. On top of the pile was a letter from the RNLI thanking her for supporting the lifeboats. “When I opened it I had to smile,” she said.

Dr Robinson had just returned to Norwich after escaping from the MS Explorer which sank in the Antarctic on Friday - in a lifeboat.

“I was dozing in my cabin at about midnight on Thursday when there was a load thud,” she said. “We had been going through pack ice so I was used to scrunching and scraping noises, but this was different. We had hit had iceberg.”

Dr Robinson, a partner at the Oak Street medical practice, had always dreamed about a trip to Antarctica, but suddenly the trip of a lifetime was turning into her worse nightmare.

“An alarm went off and all crew were called to muster station, the announcer said 'this is a real emergency'. All the passengers were told to dress in very warm clothes and go to emergency points.”

Dr Robinson put on all her warmest clothes and huddled with the 85 other passengers and 66 crew in the ship's lecture hall. She left her “money, keys and digital camera with all my holiday photos” in the cabin and they are now at the bottom of the freezing ocean along with the 38-year-old Canadian-owned ship which sank 75 miles north of the Antarctic Peninsula.

“We were told to put on our life jackets. We had put them on in an emergency drill, but I never thought we would do it for real. I wasn't particularly scared. I just felt like I was holding my breath for six hours.

“The Captain told us he had put out a mayday call, and had responses from Norfolk and Rome. When he said Norfolk, my heart dropped. I thought that's a long way from here. But it turned out to be the coast guard in Norfolk, Virginia.

“The ship started to list heavily to one side, and the captain ordered us to abandon ship. Thirty-three of us were jammed like sardines into a lifeboat. It was pretty cold floating around with icebergs for four hours. But I made lifelong friends with the people sitting next to me.

“A Danish man, who had the cabin next to mine, proposed to his girlfriend while they were in a lifeboat. The previous day he said he was going to propose to her, and I guess he didn't let the day's drama put him off. I hope we all get invited to the wedding.”

Dr Robinson, and the other passengers including 23 Britons, waited in the open-topped boats in minus 5C water until a passing Norwegian liner answered their emergency call. “The NordNorge out-classed our 'Little Red Ship'. We were taken to seventh floor in a lift. I could even check the news coverage of our drama from the ships internet café.

“I am so grateful to the captain, crew and passengers of that boat they really fantastic and could not have been more helpful. The boat was quite crowded because it was full of other passengers trying to enjoy their own cruise.”

“We were taken to a Chilean Army base on King George Island, in South Shetland, where we slept on camp beds in the soldiers' gym. There was one phone in the base which we could use to call our families. Later that night a woman phoned and asked to 'speak to someone British,' so I went to take the call. It was a journalist from the Mail on Sunday who asked me why I hadn't taken any photos of the disaster.”

Dr Robinson's epic journey was not over yet. At 7pm on Saturday she was flown in a Hercules to Punta Arenas, in Chile, where “we were greeted by the British counsel and representatives of the dozens of other nationalities on the ship. There were so many journalists there when we landed. A woman from The Sun even tried to interview me while I was in the toilet.”

She then took a flight to Santiago, then another to Buenos Aires in Argentina, a connecting flight to Madrid, before finally touching down in Gatwick on Tuesday night.

“We were only two-thirds of the way through our trip when the ship sank. I'd like to go back and complete the trip, but I'll need a little time to recover first.”