China's National Stadium, nicknamed the "Bird's Nest" and one of the two iconic venues for this year's Beijing Olympics, hosted its first sporting event on Friday.
Australian Jared Tallent was the first athlete to taste victory in the arena when he won the IAAF 20km race walk.
Here are five facts about the stadium:
* Construction began on Dec. 24, 2003, the same day as the neighbouring "Water Cube" National Aquatics Centre. The first sporting event was held on April 18, 2008, 112 days ahead of the opening ceremony.
* Occupying 258,000 square metres and seating 91,000 people, it will stage the opening and closing ceremonies, athletics competition and soccer finals during the Games.
* It cost 3.5 billion yuan ($500.7 million), used 42,000 tonnes of steel and involved the relocation of 4,707 residents from 2,043 households in the surrounding area.
* Construction was suspended in 2004 after complaints that it was costing too much. Some 9,000 seats, 12,000 tonnes of steels and the retractable roof were cut from the design. Further delayed for 14 weeks because, officials said, of the complexity of preparing for the opening ceremony.
* After the Games it will become the home stadium of Beijing Guoan Football Club and an auction will be held for the naming rights. It will cost 40 to 50 million yuan ($5.72 million-$7.15 million) a year to run.