The Duke and Duchess of Cambridge visited the Tata Steel plant in Port Talbot to learn about the importance of the operation to UK manufacturing - from food cans to warships and cars.
The couple wore protective clothing including hard hats, goggles and a jacket for their guided tour of the plant's Hot Strip Mill.
The royals watched as ingots of steel were heated and passed through rollers which reduced their size in a process that produced a loud rumble and huge plumes of steam.
Tata announced in November it would be cutting up to 1,000 UK jobs, part of a total reduction of up to 3,000 across Europe.
Earlier today, the duke and duchess visited Mumbles where they were greeted by large crowds of well-wishers.
The couple paid a visit to the RNLI's Mumbles lifeboat station overlooking Swansea Bay, one of Wales' busiest.
They also spoke to crew members about day-to-day life as part of a team that provides 24-hour rescue services at sea.
During the tour of the lifeboat station, William presented James Bolter with a medal to mark 20 years of service.
The duke and duchess also spoke with Paul O'Dwyer who was rescued by the crew last summer after his yacht broke down.
They then watched the lifeboat launch as a part of a training exercise, before walking back down the pier to meet many of the hundreds of members of the public who had gathered to see them.
After leaving Mumbles pier, the couple visited Joe's Ice Cream Parlour on the nearby sea front.
They met directors of the company, which is in its fifth generation, before being served ice cream by staff.
William was served a chocolate ice cream, while Kate had a vanilla ice cream in a cup with a wafer - the same served to five nursery children she and William met in the shop.
She pointed to her ice cream and said "snap" to the children, before telling them she did not think she would be able to finish all of her larger portion.
As the couple left the ice cream parlour, Kate hugged two of her teachers from her former prep school.
Denise Alford-Evans and husband Kevin Alford had travelled from their home in Carmarthen to meet the duchess - the first time they had seen her in 24 years.
They both taught Kate, as well as siblings Pippa and James, at St Andrews Prep School in Pangbourne, Berkshire.
Kate exclaimed: "It's such a small word".