(CNN) -- The captain of the Greenpeace ship Arctic Sunrise returned home to Maine on Saturday after an absence of more than three months that included time in one of Europe's oldest prisons.
"I'm going to shovel out a path to the woodpile and get a fire going," Peter Willcox said in a phone interview shorty after arriving at his house on Islesboro Island. "That's the first thing on my list."
Willcox, 60, who joined the environmental activist group in 1981, was among 28 protesters and two journalists aboard the Greenpeace vessel who were arrested by Russian authorities and thrown in jail in September.
The 70-foot Greenpeace vessel was on a mission to protest a rig owned by Russian company Gazprom when a helicopter swooped down and paratroopers stormed the ship and arrested everyone on board. They were held in a prison in Murmansk for six weeks and then the remainder of the time in St. Petersburg, including a stint at Kresty prison, which dates back to the late 1800s.
The charges: piracy, with a potential sentence of 10 to 15 years in prison. While the charges were later reduced to "hooliganism," they were still looking at a penalty of up to seven years in jail.
"If it wasn't the conditions that were so bad for the first six weeks in jail, it was the uncertainty of being charged with piracy," Willcox said. "That was the thing that caused the anxiety, the stress and the nervousness."
Initally, the jailed activists, who became known as the Arctic 30, spent 23 of 24 hours every day in small, cold cells. They were allowed one hour a day of solitary exercise in a "concrete box" slightly larger than their cells.
"You could go for a months without seeing the sunshine and we did," said Willcox, who was the captain of the Greenpeace Rainbow Warrior when it was bombed by French agents in Auckland, New Zealand in 1985, killing one crew member.
At Kresty, Willcox said he shared a cell with a 40-something Russian charged with dealing drugs. He was isolated from his crew. The two men played chess. His cellmate also would cook and share meals with him.
"He cooked me some wonderful dinners," Willcox said. "He had a real grocery store in our cell. His family would bring him food. Greenpeace would bring me food. He has an immersion heater which he put in a coffee bowl of water with vegetables and make a good soup."
Willcox also spent time reading Harry Potter books delivered by Greenpeace.
The ordeal ended last week, with a sweeping amnesty program by Russian President Vladimir Putin. The amnesty law freed business executive Mikhail Khodorkovsky and two members of Russian punk band Pussy Riot, who were jailed for a performance critical of Putin.
"The reason we're out ... is that there was such an outpouring of support for us all over over the world, from people like Paul McCartney and Nobel laureates and senators," Willcox said. "We'd still be in jail if we hadn't had that kind of support."
Another big reason: In less than two months the world attention will be on Russia's Sochi Olympics.
"I'm quite convinced the government didn't want is in jail during the Olympics," Willcox said. "That would have been a huge mistake. There would have demonstrations at the Olympics which they didn't want. It just wasn't worth the trouble to keep us."
Willcox said he remains committed to Greenpeace and its environmental cause. He said he does so mostly for his two daughters, ages 18 and 22. In February he will embark on another Arctic Sunrise mission in the United States.
"If somebody says that people in Russia and people around the world are much more aware of the dangers of drilling for oil anywhere, and especially in the Arctic, I'd say, 'OK, I can do two months for that,'" Willcox said. "What I couldn't do for that is 10 to 15 years... To me the alternative of turning the world over to the oil companies is not a viable option."