The 15 Most Expensive Megaprojects In Modern History

king abdullah economic city

Photo: moveoneinc.com

The most expensive large-scale projects in the world range from airports to entire city districts.  

While some changed a lot of lives for the better, such as public transit systems, others are just billion-dollar eyesores, like the never-completed Dubailand.

We’ eve ranked the top 15 according to their inflation-adjusted cost using this calculator.

15. The John F. Kennedy Airport Expansion

Inflation-adjusted cost: $12.7 billion.

Cost in 2001: $10.3 billion

New York's JFK airport is among the busiest in the world. The airport's comprehensive expansion a decade ago included building new terminals and constructing an 8-mile-long AirTrain to make it public transit-friendly.

Source: The Port Authority of New York and New Jersey

14. The Second Avenue subway expansion

Inflation-adjusted cost: $17.9 billion

Cost in 2007: $17 billion

This subway line on the east side of Manhattan has been in the works for 75 years but delayed because of funding problems. Developers broke ground on the project in 2007.

Source: New York Magazine

13. Channel Tunnel

Inflation-adjusted cost: $22.4 billion

Cost in 1994: $15.4 billion

This amazing underground tunnel takes high-speed railways 31.4 miles underneath the English Tunnel into France. In 1996, it was named one of the Seven Wonders of The Modern World.

Source: The Los Angeles Times

12. The Airbus A380

Inflation-adjusted cost: $23 billion

Cost in 2005: $22 billion

The Airbus A380 is the world's largest passenger airline, designed in an attempt to one-up the company's archrival, Boeing. It flew for the first time in 2005. One plane retails at $300 million.

Source: FlightGlobal.com

11. Toei Oedo line

Inflation-adjusted cost: $23 billion

Cost in 2000: $18.4 billion

The Toei Oedo subway line was Tokyo's first linear motor metro line, meaning it could carry smaller passenger cars. It took nearly 10 years to build and is the world's most expensive subway.

Source: Wikipedia

10. Big Dig

Inflation-adjusted cost: $23.1 billion

Cost in 2007: $22 billion

The Big Dig tunnel in Boston rerouted Interstate 90, the chief highway, through the heart of the city. It was completed 10 years late and because of design flaws and leaks the builder had to pay $407 million in restitution. It won't be paid off until 2038.

Sources: The Boston Globe

9. Beijing–Shanghai High-Speed Railway

Inflation-adjusted cost: $26.1 billion

Cost in 2008: $25.8 billion

This railway connects two of China's biggest cities is the longest high-speed railway ever to be constructed in a single project. Trains go upward of 200 miles per hour, meaning you can go from one city to another in 4 hours, 48 minutes.

Source: The Telegraph

8. Hong Kong International Airport

Inflation-adjusted cost: $27 billion

Cost in 1998: $20 billion

Hong Kong's main airport is one of the busiest in the world and employs 60,000 people. In 2011, 53,314,213 passengers went through the airport.

Source: Airports Council International

7. Kansai International Airport

Inflation-adjusted cost: $29 billion

Cost in 1994: $20 billion

Kansai International Airport operates out of the Osaka Bay in Japan. The airport is actually located on a man-made island that engineers designed to withstand the earthquakes and typhoons common to the region.

Source: The New York TImes

6. Songdo International Business District

Estimated Cost: $40 billion

The Songdo International Business District is a planned Central Business District in Seoul, South Korea that's being built on reclaimed land. It will contain a replica of Central Park. The Business District will be completed by 2020.

Source: The Independent.

5. Dubailand

Inflation-adjusted cost: $76 billion

Cost in 2003: $64 billion

Dubailand was launched in 2003 and was supposed to include 250 projects including a Disney theme park, an IMAX theatre, a Six Flags park and a shopping mall. The developers collected $55 billion in private funding for the project. But construction was halted in because of the country's financial crisis in 2008 and hasn't resumed.

Source: Yaverde.com

4. California High-Speed Rail

Estimated Cost: $98.5 billion

The California High-Speed Rail is a project that will connect cities all over the state from Sacremento to Los Angeles by public transit. Construction will begin in September of this year.

Source: California High-Speed Rail Authority.

3. King Abdullah Economic City

Inflation-adjusted cost: $95 billion

Cost in 2005: $86 billion

King Abdullah economic city is supposed to solidify Saudi Arabia's reputation as a business centre. In all, the project will include six cities and will house four million people. The estimated completion date is 2020.

Source: ic.gov

2.The International Space Station

Cost to date: $150 billion.

The International Space Station orbits Earth and is used as a lab to conduct experiments in physics, biology and astronomy. Astronauts from around the world have lived there for 11 years.

Sources: The Space Review

1. The Interstate Highway System

Inflation-adjusted cost: $459 billion.

Cost in 2006: $425 billion

The Interstate Highway System was started in 1955 to make the whole U.S. accessible through highways. It includes 46,876 miles and its estimated that one-third of all miles driven are on the system.

Sources: USA Today and The Federal Highway Administration

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