Stuttgart 21

Stuttgart 21 is 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 Hauptbahnhof, amongst some 57 kilometres (35 miles) of new railways, including some 30 kilometres (19 miles) of tunnels and 25 kilometres (16 miles) of high-speed lines.

The project was officially announced in April 1994. Construction work began on 2 February 2010. As of March 2013, total costs are officially estimated at 6.5 billion euros, the previous estimate being 4.5 billion euros in 2009. Heated debate ensued on a broad range of issues, including the relative costs and benefits, geological and environmental concerns, as well as performance issues.

The expected date for start of operation in 2021 (estimation in 2017) with an initial estimation of 2019 (made in 2010).

The concept attempts to combine plans for high-speed links from Stuttgart to other cities with the improvement of local infrastructure and replacement of the current terminal station. The current 17-track station is to be replaced by an underground 8-track through station.

The new tracks are planned to cross below ground at right angles to the northern end of the existing building. Parts of the historic Paul Bonatz Hauptbahnhof building, the platforms and approach tracks would be demolished, and the land sold for development.

The plans include new surface and underground lines connecting the station in Stuttgart’s enclosed central valley with existing lines. The Stuttgart–Wendlingen high-speed line running through a new tunnel, the Filder Tunnel, would connect the replacement Hauptbahnhof with a new Filder station (Filderbahnhof), serving the Airport, the Messe (trade fair) and the Filderstadt district. The line would then connect to the planned Wendlingen-Ulm high-speed line. The carriage sidings would be moved to the area of Untertürkheim station to clear land for redevelopment.

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