Five Britons detained in Russia as part of the so-called "Arctic 30" have arrived home in the UK.
The five were arrested amid claims of hooliganism following a protest about oil drilling, and held in jail for two months.
They have since been granted amnesty under a new Russian law.
Greenpeace member Anthony Perrett, 32, of Newport, South Wales, arrived in London with fellow activists Alex Harris and Phil Ball, crew member Iain Rogers and freelance videographer Kieron Bryan.
They left St Petersburg earlier today and arrived in Paris this afternoon before travelling to London's St Pancras station on Eurostar to be met by their families.
Ms Harris said being imprisoned had been "terrifying" but that she took comfort from knowing she was one of 29 other people in the same situation.
And she told Sky News she would not give up on the Arctic: "I've gone through a lot for this campaign, I'm not going to stop now."
The activists were onboard the Arctic SunriseMr Perrett told reporters: "It has been a strange few months, but it is over now and it is good to be back. We're
very relieved to be home, it's good to be back and speaking English, which has been sorely missed."
Asked whether it had been worth it, he said: "Well, look at the media that's here today. We're trying to spread the word to save the Arctic and I think we have done that job fairly well."
Ms Harris said she thought the Russian government let the Arctic 30 go to avoid global criticism in the lead up to the 2014 Sochi Winter Olympics.
A sixth Briton, activist Frank Hewetson, has also been released and is travelling to another country.
The Arctic 30 - 28 activists and two freelance journalists - were arrested after Russian authorities boarded their ship, the Arctic Sunrise, during an anti-drilling demonstration in September.
The group were detained for protesting against an Arctic offshore oil rig owned by the Russian company Gazprom.
They were initially charged with piracy, but the charge was later changed to hooliganism.
They had their passports returned to them after being freed on bail by courts in St Petersburg, but initially did not have visas to leave Russia.
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