With the global population continuing to expand and with our world facing immense challenges from housing to transportation and our use of natural resources, super-sized construction projects have begun to proliferate.
With eye-watering budgets, extreme complexity, staggering scale and far-reaching impacts, these are some of the world's most impressive megaprojects.
As the demand for air travel continues to grow, and with the United States preparing to host both the 2026 FIFA World Cup and 2028 Olympic Games, airports across the country — from LaGuardia to LAX — are undergoing multi-billion-dollar overhauls.
The USD $8.5BN upgrade to Chicago's O' Hare International will mark the first comprehensive redevelopment and expansion of the terminal core in the airport's history.
The masterplan will see Terminal 5 expanded while Terminal 2 will be completely rebuilt, becoming a global transfer hub with two satellite concourses, adding 280,000 square metres of space and 50 additional gates to the airport.
To minimise disruption, the new concourses will be built first, allowing them to take over operations from Terminal 2 when the existing building is demolished.
Work on Terminal 5 is scheduled to complete by 2022 and subsequent phases will open in stages up to 2028. A joint project between 35 nations, the ITER (formerly known as the International Thermonuclear Experimental Reactor), is currently under construction in France.
Once completed the USD £20BN centre will allow scientists to recreate the fusion reactions that take place inside the Sun, potentially revolutionising energy production.
Consisting of three main buildings, the project is centred around the tokamak, a magnetic chamber that will contain the plasma created when particles are heated to over 150 million degrees Celsius and collide to produce fusion energy.
Construction of the vast building that houses the reactor began in 2013, requiring the development of 10 different types of concrete to shield workers from radiation.
