Skypark
Back in 1984, the late Prime Minister General Prem Tinsulanonda (the former head of the Privy Council who served as Regent of Thailand for a period of a few months between the reigns of Kings Rama IX and X in 2016) ordered the construction of a Skytrain line, the contract of which was awarded to a Canadian company called Lavalin International Co.
The project was meant to cover 98 km over three separate lines, but the project was scrapped in the 1990s during the Asian Economic Collapse. The partially-completed Skytrain bridge across the Chaophraya River lay abandoned for decades... until this year. This year, the city opened the world's first skypark - a public park built on an artificial landmass spanning across a river. The old abandoned Skytrain bridge has been rebuilt into a beautiful public park!
The Skypark is really a sort of proof of concept. Similar projects were proposed and scrapped in London and New York City for being impossible. Bangkok's trailblazing Skypark proves that this really is the city of the future!