Olympic torch: Queen welcomes flame at Windsor Castle
The Queen and the Duke of Edinburgh welcomed the Olympic torch relay at their home, Windsor Castle.
The torch was carried into the castle by a rain-soaked torchbearer, Gina Macgregor, 74, who was met by London 2012 chairman Seb Coe.
Earlier, Sir Steve Redgrave, who won five consecutive Olympic gold rowing medals, took the flame down the Thames.
Sir Roger Bannister carried the torch in Oxford, where he broke the four-minute mile in 1954.
A male streaker with "Free Tibet" written on his back ran across the front of the torch convoy while it was going through Henley.
A man was arrested at the scene and 27-year-old Daniel Leer, from Henley-on-Thames, was later charged with indecent exposure.
It was a dramatic day for the Olympic torch relay, which made its royal visit just after lunch.
The Queen walked through the castle grounds with Lord Coe to meet pupils from Desborough School and other children who had made their own paper torches.
Thousands of people flocked to the castle to catch a glimpse the torch, lining the long avenue leading up to the castle's entrance. They were able to see it come out of the castle, carried by Alan Corbishley who jogged the entire way.
Earlier, Britain's greatest Olympian, rower Sir Steve Redgrave, rowed one-handed with the torch on the Thames.
Sir Steve's boat at Henley was crewed by six local youngsters and they crossed the river to his boat club, Leander, just after 09:30 BST. The cox was BBC rowing commentator Garry Herbert, who won Olympic gold with the Searle brothers in 1992.
"To have my hands on the torch is pretty special. It's surreal - when I retired in 2000 I was asked to come on to the bid team," said Sir Steve.
"What we were working towards were the Games in 2012 and now it's just 18 days away."
Another sporting knight of the realm, Sir Roger Bannister, carried the flame in Oxford's Iffley Road stadium, where he ran into the history books as the first athlete to run a mile in under four minutes.
Sir Roger, 83, who was the day's first torchbearer, said it was an honour to be on the list of those carrying the torch and added in 1954, as now, the weather was uppermost in people's minds.
"That day the weather was so bad that I nearly decided not to attempt it," he said.
"In retrospect I'm glad because if I hadn't attempted it that day I might not have had another chance."
Celebrity chefs Heston Blumenthal and Raymond Blanc were added into Tuesday's torch mix, the latter tweeting: "I simply feel Olympian!"
The Olympic flame also visited Eton Dorney Lake, the venue for rowing and canoe sprint at London 2012.
It was carried by Sarah Winckless, who won bronze in the double sculls at Athens 2004 with her rowing partner Elise Lavericat.
Later, after the Royal engagement, it was carried at Ascot by Sydney 2000 heptathlon gold medallist and Atlanta 1996 bronze medallist Denise Lewis. She passed the flame to Frankie Dettori, the jockey who made history at the course in 1996 when he won all seven races in one day.
Speaking on BBC Radio Berkshire, he said: "It was emotional, quite overwhelming and quite scary because Monsignor [the horse] was getting a bit frisky."
Former England football captain Ray Wilkins was also among Tuesday's 111 bearers.
London 2012 Olympic torch relay
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The day's last torchbearer was Quentin Gunderson who works for a charity-run school for pupils in educational crisis and has challenged himself to run the equivalent of 40 marathons in his 40th year to raise funds.
He carried the flame into the evening celebration and lit the cauldron at the Madejski Stadium in Reading, where the city's football club, just promoted back to the Premier League, and Premiership rugby union club London Irish play.
The route travelled through Oxford, Abingdon, Wallingford, Crowmarsh Gifford, Nettlebed, Henley-on-Thames, Bisham, Maidenhead, Burnham, Slough, Windsor, Egham, Ascot, Bracknell and Reading.
A total of 8,000 people will carry the flame during its 8,000 mile, 70-day journey to the opening ceremony of the Olympic Games in London on 27 July.