Race Across the World - Season 4

The race begins in Sapporo, the capital city of Hokkaido, the most northerly of the four main islands of Japan. To reach the first checkpoint in Nara City, the teams face 1,600 kilometres through one of the most expensive countries where only a small percentage of the population speak English. With a myriad of routes to choose from, they must use all their skills, ingenuity and determination to make it off the island and to the checkpoint. 

The race to Lombok is well underway and less than five hours separate the teams. Leaving Nara City, they must cross their first border into South Korea to reach the second checkpoint in the seaside town of Sokcho. It's a leg of two halves, with the teams first having to navigate another stretch of budget-busting Japan to reach the ferry port and balance their speed and spending with the opportunity to earn. The second half will see the teams race the length of South Korea, famed for its kimchi, K-pop and taekwondo yet revealing a country that offers so much more.

After racing through the neon-lit streets of ultra-modern Japan and South Korea, there is a split in the pack. The teams enter south east Asia for the first time, starting the third leg from the chaotic Vietnamese capital Hanoi. The competition intensifies as the team in last place faces elimination. They must race over 2,000km through Vietnam and into the Kingdom of Cambodia to reach one of the fastest-developing cities in South East Asia – Phnom Penh. In a leg where every decision counts, they can choose the more popular tourist route down the Vietnamese coast to Ho Chi Minh City – before following the Mekong River into Cambodia – or the teams could risk leaving major cities and reliable transport behind for a shorter route entering Cambodia in the north.

The teams are starting from the third checkpoint in Phnom Penh, Cambodia. It's the end of the Cambodian national holiday, Pchum Ben – meaning Ancestors' Day – and the teams have a chance to receive a blessing and pay respects to loved ones. Then the remaining pairs must leave the checkpoint and travel 1,400 kilometres through Thailand, one of the most visited countries in the world, to the Shan Highland that straddle the Thai-Myanmar border, where the fourth checkpoint is situated in the sleepy mountain town of Mae Sariang. To reach the checkpoint, the teams must first circumnavigate the Tonle Sap Lake and decide whether to head west, taking on potentially faster routes, or opt for the eastern route, where lies Siem Reap, the gateway to Angkor Wat. But from there it's a journey back in time through Thailand's rural eastern provinces, and a longer and circuitous route rarely travelled by backpackers.

The teams must navigate the full length of Thailand to reach the next checkpoint - Koh Phi Phi - an archipelago of islands immortalised by the Hollywood blockbuster movie The Beach. Their first challenge is to get to Bangkok, but with very limited transport out of sleepy Mae Sariang, this is not going to be as straightforward as they might think. With every decision counting, they will need to exercise ingenuity and race smart. They could take the familiar backpacker route and detour north via Chiang Mai, Thailand's second city, where they can make the most of the abundant transport options. Or they could navigate the lesser travelled route, hugging the Myanmar border via the city of Mae Sot. Once they reach the capital, the teams face more decisions – do they travel quickly through, or stop to take in the sights of the vibrant Thai capital? Every decision counts. As they edge closer to Koh Phi Phi, travelling south along the elephant's trunk of Thailand, our racers must decide whether to choose Krabi or Phuket to travel through and how to make the final run into checkpoint - speedboat or ferry – a decision that could make the difference between coming in first or last.

After enjoying the tranquillity of the paradise islands of Koh Phi Phi, the teams now face a giant leap into the unknown, leaving Thailand behind to embark on a 2,000km journey across Malaysia to the rarely visited Indonesian island of Sumatra, where the sixth checkpoint lies in the mountain-fringed city of Bukittinggi. Our intrepid duos will need to decide whether they want to island hop via Koh Lipe, maximising their time on Thailand's white sandy beaches but likely to put a strain on their budget, or go back to the Thai mainland to make the most of cheap and frequent transport links down the Malay peninsula. At this stage in the race, with budgets dwindling and the pressure mounting, every decision counts.

The teams must travel through the populous Indonesian island of Sumatra, where they will endure an ad-hoc transport system, limited accommodation options and virtually zero English spoken.

Twelve minutes is all that separates the first two teams as they embark on the final leg of their Race Across the World from Jakarta to Lombok.

The five intrepid teams reunite in London to look back at their 51-day thrilling adventure through some of the most beautiful, populous and remote places on the planet.