Rob McArthur and Poldy van Lyden swam the English Channel on Sunday, clearing a major hurdle in their Arch2Arctic expedition to raise £100,000 for UK Scouts. McArthur completed the swim in 12 hours and 40 minutes, while van Lyden took 18 ½ hours, joining the small group of 1,832 people who’ve swum the channel solo. The two men are aiming to travel from Marble Arch in London to Svalbard in the Arctic, some 5,000 kilometres, by human power alone. For the next stage of the journey, they’ll be taking to their bicycles. UK Scouts made this video of their incredible swim from Dover to Calais.

You can track McArthur and van Lyden’s progress on arch2arctic.com , on Twitter @Arch2Arctic and on Facebook.