Their Royal Highnesses at St Illtud's Church in Llantwit Major where they viewed the 1,000 year-old Celtic crosses which are housed there
The Prince of Wales is admiring the old and new today with visits to Britain's earliest centre of learning and a cutting-edge factory manufacturing credit card sized computers.
Their Royal Highnesses are enjoying the second day of their annual summer tour to Wales.
Yesterday, The Prince embarked on a hat-trick of events by visiting three family businesses and today the Royal Couple will complete six engagements.
Their Royal Highnesses kicked off their busy day at the newly restored 13th Century St. Illtud's Church in the Vale of Glamorgan.
The church, in Llantwit Major, was founded in 500AD by the Welsh monk Illtud and is believed to be Britain's earliest centre of learning.
At the western end of the church stands the Galilee Chapel, which was originally a two storey building but became a roofless ruin after years of neglect.
The Galilee Chapel Project successfully raised funds to reconstruct the Chapel and it has been brought back into use as a visitors' centre for exploring the origins of Celtic Christianity. It now holds one of the most important collections of Celtic Christian stones in the UK.
During the visit, The Duchess held onto The Prince as the Royal couple ventured down ancient steps.
The Prince of Wales visits SONY's UK Technology Centre
The Prince of Wales tries out the equipment at SONY
They were greeted in Llantwit Major by dozens of schoolchildren and locals, who lined the streets as the local Royal Air Force band played.
Milly Harry, three, wore a crown for the occasion but became shy upon meeting The Duchess at Gilly Beans playgroup.
Reverend Huw Butler showed the couple around the restored grounds and led a 10 minute service for them.
"Today history is being made," he said.
"As far as we know this is the first Royal visit for this church."
The Prince asked whether the Celtic Christian stones had attracted many visitors and was told tourists from America and Australia had already travelled to see them.
The couple left the bright sunshine of Llantwit Major after being presented with a wicker hamper filled with local produce.
The Prince then visited Sony UK Technology Centre in Pencoed, Bridgend, Wales, marking the 40th anniversary of the factory.
His Royal Highness played a key role in bringing the factory to Wales after suggesting a plant in the country to Akio Morita in 1972 while on tour to Japan.
The factory, in which Sony employs 340 people, produces broadcast and professional cameras and The Prince was keen to get behind the lens.
He first picked up a Sony HDC2500 broadcast camera - a model used in the World Cup - and swung it towards media covering the visit.
"It's heavy," he exclaimed.
He met factory workers around the site, including team leader Julie Bunney, 34, from Gilfach Goch, who started working at the factory aged 17.
"It was a honour to meet His Royal Highness, I was so excited about it," Ms Bunney said.
"I was really nervous at first but I really enjoyed it and I was so honoured to meet him."
Ms Bunney leads a team of staff working on the Raspberry Pi, a £24 credit card sized mini-computer which is popular with hobbyists and developers.
"The Raspberry Pi came to us two years ago and we have made two million," she added. "We make one every 11 seconds."
After admiring the Pi, The Prince was introduced to Sony's range of stills cameras - and picked up one to take a photograph of the Sun's royal photographer, Arthur Edwards.
"It's quite heavy, isn't it?" he asked Mr Edwards.
"This is a change for me," he said as he aimed the camera towards Mr Edwards and pretended to take a shot.
"You look much better on the screen," he joked.
The Prince was also intrigued by Wales Interactive, a games developer based on the second floor of the sprawling Sony site.
Entrepreneur David Banner, managing director of the company, told His Royal Highness how they had produced the first Welsh language game.
"That looks terrifying", The Prince said as he watched a developer create characters for a game.
His Royal Highness was also given a screening of First World War footage, which has been restored by Dragon. He also watched footage taken inside a steelworks in 1947.
In a speech made as he unveiled a plaque at the factory, The Prince paid tribute to Sony and congratulated the company on 40 years in Wales.
"I am thrilled to have this chance of visiting this new plant because the old one I opened is somewhere else all together," he told assembled staff.
"They don't make televisions here anymore but you are brilliantly mending all sorts of people's broken or bent equipment and I was so impressed how you can find out the fault within five minutes and put it right.
"That makes most of us feel rather ashamed I think with our inability to handle all of this technology. Not only that, but the fact you make such high quality and high performing cameras, which I've found myself usually at the other end of these things so I'm all for the quality being improved."
His Royal Highness was presented with a high-definition Sony camera to take home with him.
"Maybe I'll have to send the home movies back here to be mended," he joked.