Former PE teacher Helen Glover and Heather Stanning, a Royal Artillery captain, have won Team GB's first gold medal of the London 2012 Olympics.
Rowing in the women's pairs, they stormed into a quick lead which saw them ahead of the rest of the field by a length.
At the half-way stage New Zealand were their closest competitors but they were well back.
The noise of the crowds at Eton Dorney, which included the Duke of Cambridge and Prince Harry, increased the closer to the finish line Glover and Stanning came and with 500 metres to go they appeared to have annihilated the rest of the field.
The length of their lead shortened in the final moments as they realised victory was assured but they still crossed the line in 7min 27.13sec at which point they both punched the air and embraced in the boat.
Australia sneaked into the silver medal position with New Zealand taking bronze.
The victory on the fifth day of the Games finally eases the concerns of British fans who have been growing increasingly anxious at the lack of gold won by the host nation.
And those fans will be hoping it sparks a gold rush for Team GB, where further medals are expected later today in the rowing and cycling events and possibly in the gymnastics and the pool.
While Britain is known for its supremacy in rowing, gold has always been the reserve of the men. With victory today Glover and Stanning have become the first British women to win an Olympic gold medal in rowing.
It caps a brilliant year for the pair who have won gold at all three World Cup events this season and cantered through the heats in an Olympic record time of just under 7 minutes.
Speaking to the BBC after the race, Stanning said: "I'm absolutely shattered and absolutely ecstatic all at the same time.
"I want to collapse but I'm just so overjoyed, I just want to jump around at the same time. I'm probably talking rubbish now."
She felt the race went exactly to plan.
"We could see from all the races we've done this season, we've got out ahead and stayed there and tried to push on the margin," she said. "That's exactly what we tried to do today."
"We wanted to keep the same margin we've had in all the World Cups."
Glover appeared to be smiling in the last quarter of the race, but she said: "It was probably a grimace. I don't remember smiling because I remember never ever ever thinking we've got this."
She added that she hoped the performance would inspire others.
"If I can do it, just take the chance - not just rowing, anything," she said. "If you work hard, and try your best absolutely anyone can do anything."
Prior to today's race, Glover had said: "This is our lake." Indeed it is, and for a moment, so is all of Great Britain.
Unfortunately, the British women's quadruple scull of Melanie Wilson, Debbie Flood, Frances Houghton and Beth Rodford could not emulate Glover and Stanning in the following final, finishing sixth.
Ukraine, who were unbeaten through the World Cup series, produced a commanding performance to win gold.
World champions Germany were beaten into silver medal position with the United States taking bronze.