Kansai international airport
Moving away from tunnels we take a trip to Japan's Kansai region and take a closer look at the world's first airport to be built on an artificial island the Kansai international airport is one of Asia's busiest airports and can remain operational 24 hours a day because of its isolated location when this offshore airport was approved the location for its construction did not exist so the first step was to construct an artificial island that can hold a world-class airport construction work on this man-made island and the future airport destination started in 1987. a 30 meter layer of earth was laid on top of the water by crushing three mountains and pouring them into a seabed consisting of thousands of heavy sandpipes the result was a 4.5 kilometer long and 2.5 kilometer wide artificial island which was completed in 1990. the airport was finished four years after that and was officially opened in 1994 after some modifications repairs and the addition of a second runway the total costs had risen to 24 billion dollars however the novel location and engineering innovation made the Kansai international airport an instant hit more than 28 million passengers used Kansai international airport in 2019 and it ranked third in japan behind Tokyo airport and Narita international airport however it's still quite some way behind Beijing's capital international airport that crossed the 100 million passenger mark during that same year keeping that in mind expansions are underway which will enable the airport to accommodate 40 million international passengers a year by 2025 but when it comes to the most expensive transit project.