The Duke and Duchess met heroes at Queen Elizabeth Hospital, in King’s Lynn, Norfolk, on Sunday.
The royals had earlier privately marked the Clap For Carers at 5pm, a palace spokesman said.
In their first joint engagement since post-lockdown they met staff and volunteers in a marquee set up with tables and party balloons – marking 40 years of the hospital.
The party was to celebrate birthdays for both the hospital and foundation of the NHS.
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