Olympic torch: Crowds greet flame's tour of south Wales
Large crowds have turned out in blazing sunshine to watch the Olympic torch relay make its way from Cardiff through the south Wales valleys to Swansea.
About 1,000 early risers greeted Doctor Who star Matt Smith as he ran the first leg of the relay in the Welsh capital.
And 25,000 gathered in Caerphilly to see the flame visit the town and its famous medieval castle.
Hurdler Colin Jackson, who in 1988 won Olympic silver in Seoul, ran one of the day's final legs in Swansea.
The local council estimated the turn-out on the streets of Swansea at around 20,000 people, with 10,000 more attending a celebration event in Singleton Park.Sonic screwdriver to torch
Smith ran from the historic Norwegian Church in Cardiff Bay to the National Assembly building, just before 06:30 BST - earlier than planned - and said he was "thrilled" that people had come to watch.
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"It's a great privilege to be involved. I can't quite believe people have actually turned up, I thought I would be just be carrying it around, waving to the ducks.
"I'm really excited about the summer of sport we have ahead. It's wonderful."
In a previous life the Doctor, then played by Tennant, went forward in time and carried the Olympic torch in London in 2012.
Smith passed the flame to 14-year-old swimmer Llio Roberts who is ranked top 3 for her age in Wales at the 100m freestyle.
Runners were applauded and cheered at each torch changeover and a cavalcade of cyclists and runners energetically followed the flame.
Hundreds lined the streets taking photographs, and newsagents and coffee shops did a roaring early morning trade.
Ann Taylor, 52, was up at 4am with her friend Jonna Batt, 31, to get a good vantage point.
"I've never seen Matt Smith before. He was very talkative and really polite," said Miss Batt.
Her friend added: "I think it is a really good idea to have the torch tour the country like this. It puts everybody in a really enthusiastic mood.
"I think it attracts a lot of people who might not ever pay attention to it."Redgrave's extra gold
The torch visited Dinas Powys and Barry before turning north towards Caerphilly, where hundreds of people gathered for the first in a series of nine special live editions of Blue Peter.
Presenters Helen Skelton and Barney Harwood are hitting the road for the BBC programme's Big Olympic Tour, and after each show they will be taking part in a free event for families run by BBC Learning, which will include a host of interactive activities.
Five-time Olympic gold medallist Sir Steve Redgrave was at the event and was presented with a gold Blue Peter badge which he said was "very special".
He said he'd been impressed by the crowds turning out to support the torch in Wales, adding that the Games were a great opportunity for local heroes like Dai Greene to experience winning a medal in front of a British crowd.
"To be an athlete competing on home soil has got to be very special indeed," Sir Steve told the BBC.
The flame was carried through Caerphilly Castle by Bronwen Davies who was nominated for her work raising awareness of climate change.
The 16-year-old from Ebbw Vale said it was "amazing" to take the torch.
From there, the relay moved to Pontypridd and on to the day's most northerly point in Merthyr Tydfil, deep in south Wales' former industrial heartland.
TV presenter Gethin Jones said it had been an unreal experience carrying the streets through Merthyr, his home town.
"It was such an honour to carry such an iconic symbol just down the street from where I was born," he told the BBC.
After lunch, the relay turned south from Treherbert and travelled through the Rhondda Valley to a packed Bridgend.
The relay then headed towards Port Talbot, the steelworks city that is home to the Kite Tail sculpture and will cross the Sail Bridge before the climax of the day in Swansea.
The day's oldest torchbearer, 91-year-old Betty Gray, received the flame shortly after 18:00 BST.
She has been involved with table tennis since 1939, won world and European singles titles in her age group and is now president of the Table Tennis Association of Wales and still an active coach.
Less than an hour later, teenager Sophie Wheeler handed the torch to Jackson.
The 45-year-old former sprint hurdler, now an athletics commentator, won 21 major medals during his career, including 10 World and European golds - both indoor and outdoors - and two golds at the Commonwealth Games.
He set a world record of 12.91 seconds in 1993 that stood for almost 13 years and the only major title to elude him was Olympic gold, with second place behind Roger Kingdom in Seoul.
Later that evening Jackson tweeted: "That's it. I own a torch. Cheers Swansea for your support today."
The day ended with the lighting of the Olympic cauldron in Singleton Park.
It was part of Swansea's evening celebration, which saw performances from Only Men Aloud, winners of the BBC's Last Choir Standing competition in 2008 and rock band Kids in Glass Houses.
A total of 8,000 people will carry the flame on its 8,000 mile, 70-day journey around the UK to the opening ceremony of the Olympic Games on 27 July.