Their Royal Highnesses have begun a five-day visit which will see them undertaking a variety of engagements, including events relating to the complex 20th century histories of each country, and opportunities for the Royal couple to meet young people, from entrepreneurs, to mental health campaigners, and bright young talents in music and the arts.
The Duke and Duchess received a warm welcome at Warsaw Airport as they stepped onto Polish soil with their children Prince George and Princess Charlotte.
At the Presidential Palace, Their Royal Highnesses were officially welcomed by President Duda and the First Lady.
The Duke and Duchess of Cambridge visited the Warsaw Rising Museum, which is dedicated to the uprising of 1944 which saw the Polish resistance Home Army attempt to liberate Warsaw from German occupation.
The Royal couple met young Polish entrepreneurs pitching their ideas during a reception at Warsaw's Spire building.
In the evening, Their Royal Highnesses attended a Garden Party at the Orangery in Lazienki Park, where The Duke gave a speech.
Catherine and I are delighted to be embarking on our first visit to Poland, and we hope to return many times in the years to come
On Day Two, The Duke and Duchess visited the former Nazi German Concentration Camp Stutthof, which is located in northern Poland. Stutthof was the first Nazi concentration camp set up in Poland in 1939, and was one of the last to be liberated in 1945.
110,000 people were imprisoned in Stutthof, 65,000 of whom died as a result of executions and horrendous living conditions.
Their Royal Highnesses then travelled to Gdansk town centre to experience a traditional Polish market - and a very big welcome.
Day three started with saying goodbye to Poland.
The Duke and Duchess, accompanied by Prince George and Princess Charlotte, then travelled to Berlin where they received an official welcome from German chancellor, Angela Merkel.
The first stop in Berlin was the iconic Brandenburg Gate, which has become a symbol of the unification and freedom of the city.
At the Holocaust Memorial The Duke and Duchess were shown round the Information Centre by its Director, Uwe Neumärker. The Centre shows documents, family photographs and maps showing the extent of the Holocaust.
The Duke and Duchess then travelled to Strassenkinder, a charity that supports young people from disadvantaged backgrounds, providing welfare assistance, education and sports activities.
At the Bellevue Palace Gardens The Royal Highnesses had a meeting with the Federal President, Frank-Walter Steinmeier.
Day three of The Royal Tour finished with a Queen's Birthday Garden Party, held at the Ambassador's Residence, where The Duke gave a speech and delivered a message from The Queen.
Our visit will reflect, and I hope reinforce, the strong and wide-ranging ties between Britain and Germany. - The Duke of Cambridge
After spending their first day in Germany in Berlin, Their Royal Highnesses then travelled to the German City of Heidelberg.
In Heidelberg The Duke and Duchess visited the the German Cancer Research Institute, where they met some of the leading researchers including, Nobel Prize winner Professor Dr Harald zur Hansen.
Accompanied by the Mayor of Heidelberg, Their Royal Highnesses toured the traditional German market in Central Square.
Heidelberg is Germany's oldest city and is twinned with the UK town of Cambridge. While in Heidelberg The Duke and Duchess each acted as a cox on a boat in a competitive rowing race between Heidelberg and Cambridge.
The winning team was congratulated at the finish line - which was in a beer garden.
The final day of the tour started in Hamburg, where The Duke and Duchess visited the Maritime Museum to celebrate the joint UK-German year of science.
At the Elbphilarmonic Concert Hall, one of the biggest concert halls in the world, Their Royal Highnesses listened to a special performance by the Hamburg Symphony Orchestra for the children of Hamburg.
The Duchess was then invited to have a go at conducting herself.
The final event of the tour was a visit to Airbus, where Their Royal Highnesses toured training facilities and met apprentices, before viewing the final assembly line of an A320 aircraft.
Do widzenia and Auf Wiedersehen - Thank you for a wonderful visit!