This is their their first overseas royal tour since becoming a family of four, and they will be visiting India and Bhutan between 10 and 16 April.
The devoted mother and father have left their two cute little ones, Prince George and Princess Charlotte, behind for the first time, shortly after going on a family ski trip together.
Unlike his father, who's been to the country on eight official tours, William has never visited the region, and neither has Kate. William's mother Diana, Princess of Wales, also visited India in 1992, so the royal will be following in both parents' footsteps.
Follow their journey below!
Day 5: Kate and William give archery a go in Bhutan
Kate and William left India on the fifth day of their royal tour to visit Bhutan.
The Duke and Duchess of Cambridge arrived looking happy and refreshed, with Kate wearing a floaty peach dress and nude accessories.
The British royals were welcomed to the latest leg of their tour by King Jigme Khesar Namgyel Wangchuck and Queen Jetsun Pema of Bhutan – who are dubbed the ‘Kate and Wills of the Himalayas’, as Queen Jetsun has a similar background to Kate, being the daughter of a pilot.
Following a colourful parade, one of their first engagements was to watch the national sport of Bhutan, archery - and Kate and William even had a go themselves, after being invited to try their hand at hitting a bulls eye.
William went first, but after missing twice he happily handed the reigns over to Kate. Despite his less than perfect record he was quick to offer his wife advice, saying: ‘You’ll be fine. You should try to shoot up in the air.’
Kate’s arrow went about 20 yards, but the Duchess didn’t seem to mind as she fell into a fit of giggles before apologising for her efforts.
During William's archery the crowds were chanting songs, and when asked to explain what they were saying Sonam Karma, a Bhutanese Olympic Committee official said, 'They are singing obscenities. You’re bald. You’re a baldy. Your nose is really big. We hope your private parts are as big.'
It turns out that these less than complimentary chants are traditionally sung to put opponents off!
Kate seemed to be popular with spectators as one little boy blew the Duchess a kiss.
That evening Kate and WIlliam joined the King and Queen of Bhutan for dinner, with Kate wearing a maxidress from Tory Burch, an American designer.
Day 4: Kate and William set off on safari, visit an animal sanctuary and get creative
It's day four of the couple's royal tour, and today the pair have been pictured enjoying a guided safari of the Kaziranga National Park.
Smiling and waving to onlookers as they're driven in a Jeep, they both look dressed for the occasion - Kate was sporting brown skinny jeans, a white cotton shirt and flat shoes, while Wills looked casual and comfortable in chinos, a beige shirt and brown lace-up shoes.
The couple, who were given white scarves featuring the print of some of the endangered animals of the park – rhinos, deers and birds - looked excited to be getting a glimpse of the World Heritage Site and wildlife conservation area. It's home to elephants, water buffalo, swamp deer, tigers, and two-thirds of the world population of Indian one-horned rhinoceroses.
The pair later got up close and personal with the animals at a local sanctuary within the park, where they were pictured feeding baby elephants and rhinos.
Vivek Menon, chief executive office of the Wildlife Trust of India, said, 'They were absolutely thrilled and loved being with the animals. The Duchess loved the baby rhino particularly.'
'The Duke said if he could he would have spent the whole day there.'
During their visit, Kate, who had changed into a pink Topshop dress for the occasion, admitted to 'terribly missing' her children, adding that the little girls dancing around the village reminded her of 11-month-old Princess Charlotte and saying 'The next time we come, we will definitely bring them.'
When asked why they didn't bring the two youngsters on this occasion, she replied, 'Because George is too naughty. He would be running all over the place!'
After playing with the residents at the animal sanctuary, Kate and William got to try their hands at weaving cloth, and helped to decorate an elephant statue at the Mark Shand Foundation.
Day 3: Kate and William meet young people in New Delhi, have lunch with Indian Prime Minister Narendra Modi and attend a Bihu festival
Kate and William kicked off the third day of their royal tour by meeting a group of vulnerable young people in New Delhi. They learned about the work of charity Saalam Baalak, which provides care and protection to street and working children in Delhi and the surrounding areas.
The charity's director Sanjay Roy spoke to the royal pair about the charity's work: 'We look after around 7,000 kids a year, but every day around 40 to 50 new children arrive at the station. They often have to deal with trauma, learning difficulties, ADHD, and we have special programmes to help them with that.'
Prince William asked: 'What can we do to help?'
Mr Sanjay said: 'Spread the word. People think of them as street kids, beggars, thieves, but they are just children. They deserve an education, future and a life. They have a right to a childhood.'
Their second engagement saw Kate and Wills meet with the Indian Prime Minister Narendra Modi for lunch. Kate looked stunning in a jade green lace dress, which was from one of her favourite designers Alice Temperley. She completed the look with her trusty pair of nude heels and a straw clutch bag.
A Kensington Palace spokesman said the couple are 'grateful to have this chance' to meet the Prime Minister, adding that the tour was first announced following Mr Modi's lunch with The Queen in January.
Later that day Kate and William attended a Bihu festival by the Diphlu River Lodge in the Kaziranga National Park. The Rongali Bihu - of Bihu of Happiness - is a spring festival which marks the end of harvest and the beginning of the new year. The pair were seen laughing and dancing, particularly enjoying the energetic dancing of a three-year-old boy dressed in traditional attire.
Day 2: The royal couple travel to New Delhi, pay their respects to fallen Indian soldiers, visit Gandhi Smriti and attend a garden party to celebrate the Queen's 90th birthday
On the second day of their tour, Kate and William visited The Social, a café and collaborative work space, where they met the city's young entrepreneurs and had the chance to try out their ideas. Using one of the innovations, the couple learnt how to type in Braille and typed the word 'George'. So sweet!
The two then flew to New Delhi, where they started the day by laying a wreath at national war memorial India Gate to pay their respects to India's Armed Forces.
William and Kate make their way to India Gate memorial
Although the memorial covers four conflicts, the couple were particularly honouring the 70,000 Indian soldiers who lost their lives while fighting for the British Army during the First World War.
The royal couple layed a wreath to honour the lives of the Indian soldiers who died fighting for Britain in the First World War
In the afternoon the Duke and Duchess of Cambridge paid a visit to Gandhi Smriti, a museum dedicated to India's founding father Mahatma Gandhi. The couple also paid their respects at the spot where Gandhi was assassinated.
Kate and William had to take their shoes off at the Gandhi museum
As part of their royal tour, William and Kate paid their respects to Gandhi where he lost his life in 1948
To finish off their second day in India, Kate and William attended a garden party to honour of the Queen's 90th birthday, where they cut a birthday cake and William made a speech.
'As she turns 90, she is a remarkably energetic and dedicated guiding force for her family', William said of this grandmother. 'George & Charlotte will discover how lucky they are to have such a wonderful great-grandmother - a role model for the rest of their lives.'
The Prince also read a message from the Queen: 'I have fond memories of our previous visits to India. It is with great pleasure that I entrust another generation of my family to strengthen and renew our bonds.'
Day 1: Kate and William kick off royal tour with visit to the slums, cricket match and Bollywood fundraiser
Upon their arrival in Mumbai on Sunday 10th April, the couple were first pictured laying a wreath at the Taj Mahal Palace, which was attacked by a terrorist group in 2008. The Prince and Princess bowed their heads to pay their respects to the 31 people that were killed.
The message on the wreath read: 'In memory of those who lost their lives and those injured in the senseless atrocities at the Taj Mahal Palace Hotel. William, Catherine.' The royal couple, who are staying at same hotel, were introduced to hotel chef Raghu Deora, 41, who was shot in the stomach and in the leg as he helped guests to safety during the attacks.
The Duke asked him about what happened on the day, while the Duchess said: 'It must have been a surreal time.' Mr Deora said: 'The Duke asked me what happened to me and I explained how I was shot. He asked me how long I took to recover, and I said six months, with the last operation two years ago.'
Kate and William visited the Malabar Hill Area of Mumbai, known to be one of the city's slums, where many of the city's poorest children live next to the city's wealthiest. They enjoyed a game of football with the children, where their coach, Ashok, revealed that meeting the Duke and Duchess was a wonderful surprise, saying: 'We never thought that Prince William and Princess Kate would visit a slum and talk to the children.
'For us this is a big thing. It's like a dream come true.' Kate and William even embarked on a surprise open top bus tour of Mumbai, joining the children from slums for the journey!
The pair, who are well known for their love of sport, were then guests of honour at a cricket match, where Kate got a chance to show off her skills by taking a turn to bat.
Legendary cricketer Sachin Tendulkar - India's former captain - said of the Duchess: 'She batted, she fielded, she did everything!' adding she was 'very, very sporty'. Dressed in a flowery summer dress and nude wedges, she looked happy and at ease playing with the children alongside her husband.
Later that evening the royal couple attended a star-studded fundraiser alongside Bollywood royalty, with celebrities including Aishwarya Rai, Shilpa Shetty and Shah Rukh Khan arriving at the Taj Mahal Palace Hotel in Mumbai for the event.
The reception and dinner were held to raise funds for three charities - Magic Bus, Doorstep, and India's Childline, which support vulnerable children in Mumbai and across India.
The Duchess stunned in a blue beaded Jenny Packham gown and cape, wearing royal blue earrings by Indian jeweller Amrapali, while Prince William looks dapper in a dinner jacket and bow tie.