Laura Trott has pedalled into Olympic history as Team GB celebrated its most successful Games for a century.
Trott, 20, won the omnium in the frenzied atmosphere of the velodrome, where Prince Harry was among those cheering in the audience.
An ecstatic Trott said: "I can't believe this is happening to me, I really can't. I am so happy."
The Team GB medals tally is now 21 gold, 12 silver and 12 bronze - making this the most successful Games in terms of gold medals since the London Olympics of 1908.
With five full days of competition left it seems certain that Team GB will beat its Beijing haul of 47 medals.
It was the third gold medal of the day for Team GB. Earlier, Britain's dressage team of Carl Hester, Laura Bechtolsheimer and Charlotte Dujardin trotted to a historic victory over Germany.
And the Brownlee brothers raced to Olympic glory in one of the most dramatic races yet at London 2012. Alistair Brownlee took gold in the triathlon and his brother Jonny won bronze despite being given a 15-second penalty.
As he closed in on victory Alistair grabbed a Union flag from the crowd, wrapped it around his shoulders and walked triumphantly across the finish line in Hyde Park. He waited to embrace his brother who overcame the penalty given for mounting his bike too quickly after swimming the Serpentine.
There was further success in Weymouth as Nick Dempsey took silver in the men's windsurfing.
But Phillips Idowu, the controversial 33-year-old Beijing silver medallist, crashed out of the triple jump when he failed to jump far enough to qualify for Thursday's final.