Stuttgart 21is a railway and urban development project in Stuttgart, Germany. It is a part of the Stuttgart–Augsburg new and upgraded railway and the Magistrale for Europe (Paris—Vienna) in the framework of the Trans-European Networks. Its core is a renewed Stuttgart Central Station. The project was officially announced in April 1994. Total costs were officially estimated at 4.1 billion Euros (in December 2009) (wikilink).
Germany’s “Der Spiegel” (link) now reports that completion of the new Stuttgart railway station could be delayed until 2024 with costs now put at 6.8 billion Euros. The magazine says that the project’s funders include the federal government, the city of Stuttgart and the Land of Baden-Württemberg. All appear to be now refusing to provide any additional financing.