The National Stadium in Singapore is the only stadium in the world that can be reconfigured into three modes - football, athletics and cricket.
In "football" mode, which is also used for rugby, the stadium can house nearly 55,000 spectators. The stadium's capacity will be at about 51,000 spectators in cricket mode, and some 50,000 spectators in athletics mode.
Teoh Hai Pin, director of DP Architects, said: "It's all because of these moving tiers... It is also part of a sustainability move that we did during the design stage. Sustainability not just in terms of green, but sustainability in terms of events planning and future-proofing for all events, (to be) as flexible as possible."
This ease with which the facilities can be customised is a cornerstone of the Sports Hub design.
Its designers wanted the Sports Hub to have something for Singaporeans from all walks of life - so other than spaces for competitive sports, there is a sandpit for beach volleyball and a waterfront mall with 41,000 square metres of commercial retail space, among other facilities.
Oon Jin Teik, chief operating officer of the Sports Hub, said: "There'll be people coming here for different reasons - to play, to watch, to compete, to dine, just to relax, hang out, but we also look at the age group. And then from there - what type of events, what type of programmes we want to see. (There will be) a portfolio of different types, relevant for different segments of Singaporeans.
Much has been said about the National Stadium's dome-shaped roof, which is the world's largest. Designers said the structure was chosen because of Singapore's tropical weather.
Clive Lewis, who is the Sports Venue Design Lead at Arup, said: "All the way through the design process, we sought to reduce the weight that we're putting up (on the roof).
"So in terms of the cladding weight, the weight to the moving roof, the weight to the moving roof design, everything was, 'cut the steel weight, cut the steel weight, cut the steel weight' throughout. Very different to other stadiums we've worked on and we're very proud to have achieved that, and that's an integrated architecture and engineering process.
"We're designed the largest free-spanning dome in the world and it's probably the lightest steel structure of its kind and it has a moving roof, all integrated. It's quite a special achievement."
With the roof permanently covered, there were concerns whether Singaporeans would be able to see fireworks from the dome.
Mr Lewis added: "We have a horse shoe here, looking out towards the city. And actually you can set up three different fireworks, if you had floating pontoons of fireworks in the water. If you had three of those located, 80 per cent of those sitting inside would be able to see a fireworks display on the water body, which I think is quite important.
"I think the connection to the city is really important, to have an open end to the stadium. And the best part about concert events being hosted here and having the backdrop of the city when you see that televised, like during the National Day Parade, I think that's going to be an important part of that whole setting.
"For us, it's connecting the stadium back to the city. So when you're in the city, you will hear the noise of the Kallang Roar, coming from this shell form, a projection across the water body back into the city centre."
The Sports Hub will be open to the public during a community open house on June 27.