LONDON — The fans packed into Olympic Stadium, often sitting in the cold and rain, eagerly watching the women run, leap and throw over two days. Some wore paper Jessica Ennis masks, hurled their arms into the air and gritted their teeth as she threw the shot-put or the javelin. Others clapped furiously, and more than once, “I love you, Jessica!” could be heard in the stands.


Ennis is a local star, her face plastered across billboards throughout London, and she solidified her place by grabbing the gold medal in the heptathlon Saturday.


Whenever the announcer yelled her name Friday and Saturday, the stadium burst into a deafening roar, Union Jacks flapping in the air.


She culminated the exhausting event by bursting through the final stretch of the 800 meters with the fastest time, 2 minutes 8.65 seconds, locking in her gold medal.


The stadium erupted into thunderous noise as she fell to the ground after crossing the finish line, her eyes filled with tears. Lilli Schwarzkopf of Germany earned the silver medal and Tatyana Chernova of Russia took the bronze.


Ennis is a rare celebrity in an event that made its Olympic debut in 1984 and has struggled for visibility since the American Jackie Joyner-Kersee popularized it by winning gold medals in 1988 and 1992.


The competition consists of the 100-meter hurdles, the high jump, the shot-put and the 200-meter sprint on the first day, and the long jump, the javelin and the 800-meter run on the next day.


It can also be a difficult spectator sport. While flashy marquee events take place on the track, the heptathletes cycle through the field events. But Ennis has become one of the British team’s most visible stars.


“She’s really become the face of the Olympics in Britain,” said Aron Washer, a 20-year-old from Kent, a British flag tied around his shoulders and a beer in hand at 10:45 a.m. Saturday. “She’s a good spokesperson.”


His friend Matt Day, with a red, white and blue jacket and a beer of his own, added, “It helps that she’s pretty, too.”


Ennis, 26, has proved that the sport can be lucrative. She counts BP, British Airways, Adidas, Omega and Powerade among her sponsors. She is an active Twitter user and sells T-shirts bearing her face through her Web site, jessicaennis.net. It is difficult to roam the streets of London without being greeted by her smile or her name on the tube, or in a taxi, or in a shop.


The older of two girls, Ennis was raised in Sheffield, England. She met her fiancé, Andy Hill, in secondary school there, and they now live together in Sheffield, according to her Web site.


Ennis was introduced to track and field as a youth and continued to train through school and at the University of Sheffield. Upon graduating, she turned professional and earned a bronze medal in the heptathlon at the Commonwealth Games in 2006. She won gold medals in the heptathlon at the 2009 world championships and the pentathlon at the 2010 world indoor championships.


Ennis earned a silver medal in the heptathlon at the world championships last year, with Chernova winning gold and Jennifer Oeser of Germany taking bronze.


Even if Ennis had not won a gold medal this weekend, her crowd here was the fiercest.


“I think it’s nice she’s a good role model,” Karen Knight, a fan from Suffolk, said. “We’re just lucky to have her.”


Knight’s 13-year-old daughter, Lydia, added, “I hope she wins a medal.”


Ennis did just that, fulfilling her country’s expectations. But perhaps the cheers for Ennis were loudest a few hours north in her hometown.


“I didn’t really know what the heptathlon was before Jessica,” said Hannah Falconer, a 23-year-old student from Sheffield who made her way to London for Saturday’s competition.


“It’s a big inspiration,” said Falconer, whose face was painted with a British flag. “She’s just a girl from a small town who is now competing at the Olympics.”