Japanese Prime Minister Shinzō Abe celebrated the completion of the National Stadium in Tokyo at a ceremony formally unveiling the centrepiece of next year's Olympic and Paralympic Games.
Abe praised the efforts of those involved in the project for the 60,000 stadium, which hit early difficulties after he scrapped initial plans in 2015 because of spiralling costs.
It meant construction began 14 months later than scheduled and the venue was unable to host matches at this year's Rugby World Cup as planned.
The original design by the late Iraqi-British architect Zaha Hadid was discarded following public outcry and was replaced by a design from Kengo Kuma.
The stadium, built at a final cost of ¥157 billion (£1.2 billion/$1.4 billion/€1.3 billion), will be the main venue for Tokyo 2020.
"For this National Stadium, which will be the symbol of Tokyo 2020 Olympic and Paralympic Games, I assume there must have been many difficulties for the process of its construction,” Abe said.
"The design was changed during the process.
"It is purely the result of everyone’s ‘All Japan’ contribution and hard work, so that we finally celebrate today."
The new arena, constructed on the site of the National Stadium originally built in 1958 and which staged the 1964 Olympics, features countermeasures designed to combat the expected high temperatures in the Japanese capital during the the time of the Games.
According to Tokyo 2020, natural winds channelled into the stadium from the eaves and terraces will circulate airflow and discharge heat and moisture generated from the field and spectators.
It is claimed this will reduce temperatures inside the stadium, while 185 airflow-creating fans and a mist-cooling system will also help cool athletes and spectators.
The stadium - which will host Olympic and Paralympic ceremonies, as well as athletics - features a plant-covered facade designed to maintain harmony with the natural landscape of the neighboring Meiji Jingu Gaien area.
The eaves of the distinctive roof are made of wood gathered from the country's 47 prefectures.
The stadium was handed over to the Japan Sport Council (JSC) last month and the first public event will be held there next week.
The first sporting event to be staged at the venue will be the final of the Emperor's Cup football tournament on New Year's Day.
"We are very pleased that construction of the Olympic Stadium - a key symbol of the Tokyo 2020 Games - has now been completed; it makes us realise just how close we are getting to the start of the Games," said Tokyo 2020 chief executive Toshirō Mutō.
"We appreciate the support of everyone involved in its construction, including the National Government, the JSC and so many others."