Watch Globe Trekker online: Episode 6 Trekking in Turks & Caicos and Milford Track

Ian Wright island hops around the pristine coral atolls of the Turks and Caicos in the Caribbean. He begins his adventures on the most developed island, Providenciales, which is a real draw for tourists. After kicking back on iconic Grace Bay Beach, he enjoys a spectacular dive and then tries out the local food speciality - an aphrodisiac - conch! Heading east, Ian’s next stop is North Caicos, where he learns about the island's heritage at the Wade's Green Slave Plantation and in town meets some real island characters, who he teaches how to say Hooman Bean. He then takes a ferry to the neighbouring island of Middle Caicos, for a stunning trek along its wild and deserted north coast. On South Caicos, Ian helps out on an environmental study of the lemon shark before ending his journey on Grand Turk - renowned for its beautiful colonial architecture - in search of majestic humpback whales. MILFORD TRACK, NEW ZEALAND Zay Harding prepares to trek the Milford TrackWe then meet up with Zay Harding, who is hiking the Milford Track, the most famous and spectacular trekking route in New Zealand. To reach the remote trailhead on the southwestern tip of the South Island, Zay sails in a traditional wooden ketch across beautiful Lake Te Anau, where he starts the 3-day trek up and over the MacKinnon Pass en route to the Milford Sound. On day 1 of the trek, as Zay climbs up through the narrow Clinton River gorge, a continuous downpour of torrential rain creates hundreds of waterfalls which thunder down the towering cliffs of the gorge, causing a flood surge that forces Zay to wade up to his chest through fast-flowing waters in order to make it through to his overnight stop at the mountain lodge at the head of the gorge. On day 2 the weather transforms for Zay's climb up and over the mountains. Reaching the MacKinnon Pass in glorious sunshine, the summit of the trek at nearly 4,000 feet, Zay is rewarded with a magnificent 360 degree panorama of high mountain peaks surrounding him in every direction. On day 3, and after a long trek thousands of feet down the other side of the mountains, Zay reaches the ocean, and the end of his trek - the Milford Sound, a dramatic fjord enclosed by sheer peaks plunging thousands of feet straight down into the water, has been called the eighth wonder of the world, and is a fitting climax to one of the finest treks on earth.

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