Prince William and Kate Middleton have returned to their in-person royal duties as lockdown in the UK lifts. On Sunday, the Duke and the Duchess of Cambridge visited Queen Elizabeth Hospital in King's Lynn to commemorate the 72nd birthday of the NHS, the National Health Service in the United Kingdom.

On this special day, the royals took the opportunity to thank the members of the NHS staff, who for months have been fighting at the frontline against the coronavirus pandemic. The duo reportedly joined medical staff, operational staff, and other supporting staff of the hospital, and some retirees for an afternoon tea.

Photos from their visit to the NHS facility were posted on the Cambridges' official Instagram account showing the couple dressed in matching blue attires, the colour of the NHS, for the occasion. According to Daily Mail, Kate Middleton wore a blue shirt dress with a white collar by Beulah London. She paired it up with gold earring by Patrick Mavros and Rupert Sanderson shoes. Meanwhile, she kept her look neat with a sleek ponytail. As for the prince, he looked dapper in a blue suit.

"Today we mark the 72nd birthday of the NHS, in a year when it was needed more than ever as the nation responds to COVID-19. Today, The Duke and Duchess visited the Queen Elizabeth Hospital in King's Lynn to thank the staff for their efforts in helping their community," reads the caption alongside pictures of the couple at the Queen Elizabeth hospital.

Today we mark the 72nd birthday of the NHS, in a year when it was needed more than ever as the nation responds to COVID-19.

Today, The Duke and Duchess visited the Queen Elizabeth Hospital in King’s Lynn to thank staff for their efforts in helping their community. pic.twitter.com/4WCkugETFT

— The Duke and Duchess of Cambridge (@KensingtonRoyal) July 5, 2020

Britain's NHS is an umbrella term for the publicly-funded healthcare systems of the UK. It was established in the year 1948 comprising four separate systems of four separate countries: The National Health Service in England, NHS Scotland, NHS Wales, and Health and Social Care in Northern Ireland.

Prince William and Kate Middleton
Duchess of Cambridge Kate Middleton and Prince William ahead of a ceremony at the Commonwealth War Graves Commisions's Tyne Cot Cemetery on July 31 2017 Getty

The hospital that covers West Norfolk area, South Lincolnshire and North East Cambridgeshire will be celebrating it's 40th birthday this month. It has played a pivotal part in providing care and services during the coronavirus pandemic. It has reportedly treated 450 COVID-19 patients. Meanwhile, 46 patients have been enlisted for the COVID-19 Recovery Trial and more than 500 are reportedly included in other pandemic related research.