It links the Lower Saxon state capital of Hanover with Hamburg, running through Celle, Uelzen and Lüneburg.

The main section of the route, the line from Celle to Harburg, was opened on 1 May 1847 by the Royal Hanoverian State Railways.

It formed a junction with the so-called Kreuzbahn from Lehrte, then the most important railway hub in the Hanover region, to Celle.

[4] The first section to be upgraded for 200 km/h running was the 78.4 km (48.7 mi) long stretch of line between Langenhagen and Uelzen which was brought gradually into service from 1978 and 1984.

[5] During the preparations for Expo 2000 two new S-Bahn tracks were built between Hanover Hauptbahnhof and Langenhagen (today - Pferdemarkt station).

From 2007 to 2009 the 1,700-metre (5,600 ft)-long elevated railway (Pfeilerbahn) in the port area south of Hamburg Hauptbahnhof was torn down and rebuilt.

It had been moved in order to provide a new approach to the central station that would not be threatened by flooding or involved any track crossings.

The new route, capable of handling trains at speeds of up to 200 km/h, was to be 27 km shorter than the existing line and would reduce journey times to 60 minutes.