The final episode of the series sees Paul Murton visiting the 'Atlantic Twin' islands of Coll and Tiree. Paul begins his journey on Coll where he meets the charismatic owner of Breachacha Castle, Nicolas Maclean Bristol, a descendant of the ancient MacLeans of Coll, whose history on the island goes back to the 14th century. The population of Coll has slumped in recent years to just 200 people, but Nicolas runs a charity on the island which encourages young volunteers to come and work here from all over the world, and so this tiny, remote island has a distinctly cosmopolitan feel to it.Leaving Coll behind, Paul heads for Tiree, which boasts one of the best sunshine records in the UK. It can indeed be beautifully sunny here, but it can also be extremely windy. Tiree is one of the stormiest places in Europe and, with a gale blowing 160 days of the year, life here is always something of a battle against the elements. But resourceful locals have found interesting ways to harness the islands' assets - Tiree is one of the best places in Britain to windsurf and also to sand yacht, a relatively new sport which involves racing up and down the beach in a go-kart with a sail, which Paul discovers is an exciting - if slightly alarming - experience.To end this final Grand Tour, Paul takes a boat trip out to the iconic lighthouse on the rocky outcrop of Skerryvore.