First, Britain's Jessica Ennis won the heptathlon Olympic gold, capping seven events over two days by running the last stretch. Then — unexpectedly — the hosts got a second medal when Greg Rutherford won the long jump, and Mo Farah followed, taking the 10,000 metres.
The crowd went wild as the sounds of David Bowie's "Heroes" blared through the stadium speakers and a sea of Union flags fluttered in the stands as one victory run followed another. Prince William and his wife, Kate, were there.
"It's unbelievable," said Ennis.
"What a night for British athletics, three gold medals out of a possible three," Rutherford said.
It was a day where history was made in more than one Olympic sport.
Michael Phelps took an unprecedented 18th Olympic gold medal on the last day of his remarkable career, while Oscar Pistorius, the "Blade Runner," became the first amputee to compete in track at the Olympics. Pistorius was cheered around the track, finishing second in his 400-meter heat to advance to the next round on his carbon fiber blades.
The South African double amputee circled the oval with fans cheering him on in 45.44 seconds — good enough for second place in his heat and a berth in the semifinals Sunday night.
"I've worked for six years ... to get my chance," said the South African, who was born without fibulas. "I found myself smiling in the starting block."
Phelps leaves the sport with a record 18 golds and 22 medals overall. He won four golds and two silvers at the London Games. That's twice as many golds as any other Olympian.
When he finished, he waved to the crowd and smiled.
"I've been able to do everything that I wanted," he said.
In the final swimming event of the eight-day meet, the American men clocked 3 minutes, 29.35 seconds. Japan touched in 3:31.26 to take the silver medal and Australia finished in 3:31.58 to take bronze.
The U.S. women's team did not disgrace themselves, setting a world record when they won the medley relay in 3 minutes, 52.05 seconds — 0.14 ahead of the previous mark set by China at the 2009 world championships at the height of the high-tech bodysuit era.
In other late night swimming, China's Sun Yang made his mark by smashing his own world record in the sport's most arduous race.
Sun's 1,500-meter freestyle race did not have an auspicious start. He dived into the pool ahead of the start, apparently after hearing a noise in the crowd, while everyone else remained on the blocks. Yang glanced at the starter with a confused look, got back out of the pool and waited to see if he'd be disqualified.
In a night that featured the long and short of swimming, Ranomi Kromowidjojo of the Netherlands won the women's 50 freestyle to complete a sweep of the sprints.
In tennis, Serena Williams clinched her first Olympic gold medal in singles on the same Centre Court at Wimbledon, one month after winning her 14th Grand Slam title.
Williams fired an ace on match point Saturday to complete an easy 6-0, 6-1 win over Maria Sharapova.
Later Saturday, Williams and her sister Venus clinched at least a silver medal in Olympic doubles when they beat Maria Kirilenko and Nadia Petrova of Russia 7-5, 6-4 in the semifinals.
The day in the track and field stadium began unevenly.
While Pistorius made history, Usain Bolt made a stuttering debut, overcoming a slow start to advance to the 100-meter semifinals.
"I stumbled on the start," the 25-year-old Jamaican said. "I really didn't do a lot of executing."
Bolt dominated the Beijing Games four years ago, winning golds in world-record times in the 100, 200 and 4x100 relay — something no man had ever done at an Olympics. At the 2009 world championships, he lowered his 100 mark to 9.58, which still stands.
Hours later, fellow Jamaican Shelly-Ann Fraser-Pryce became only the third woman to repeat as Olympic 100-meter champion, beating Carmelita Jeter of the United States and fellow Jamaican Veronica Campbell-Brown.
Britain's great day started early.
British rowers were the stars at Eton Dorney west of London on Saturday morning, doubling their gold-medal haul on the final day of the Olympic regatta with victories by the men's four and the lightweight women's double sculls.
That left the host nation at the top of the rowing medals table with nine medals — four golds, two silvers and three bronzes — to surpass the country's record total of eight from the 1908 Olympics, which were also held in London.
In the only track cycling final of the day, the British women's pursuit team shattered its own world record for the second time while beating the United States to win gold.
The faultless trio of Dani King, Laura Trott and Joanna Rowsell delivered the home nation its fourth track cycling gold medal in five events. They finished in 3 minutes, 14.051 seconds to improve by more than a half-second the mark of 3:14.682 they had set earlier in the day.
In other results Saturday, China beat South Korea 39-25 to win the women's epee team event; Nicola Spirig of Switzerland outsprinted Sweden's Lisa Norden in the final meters to win the women's triathlon in a photo finish; Canada picked up its first gold of the games when Rosannagh MacLennan won the women's trampolining competition; Ilya Ilin of Kazakhstan won Olympic an weightlifting gold medal in the men's 94-kilogram division; Sandra Perkovic of Croatia won the women's discus, and Chen Ding of China won the men's 20-kilometre walk.