United Kingdom, Jan. 28 -- King Charles "will never forget" his visit to Auschwitz-Birkenau.

The 76-year-old monarch made a "deeply personal" visit to the former Nazi concentration camp where more than one million people were killed during World War Two to mark 80 years since its liberation and after wiping away tears while listening to the stories of survivors during a memorial service, he laid a wreath at the 'Wall of Death' near Block 11 of the camp.

He bit his lip and stood silently for over a minute, turning back twice to take in the moment.

And he wrote in the visitors' book: "Remembering what took place here, and those who were so cruelly murdered is a duty; a sacred duty that must be protected.

"Being here today, hearing the s...