clearance of the death zone or no man's land between the two. A temporary road, lined with barriers, was created across this zone and checkpoints were set up just inside East German territory. Proper dismantling of the entire wall began on 15 May 1990 and all border checks were abolished on 1 July 1990 as East Germany joined West Germany in a currency union. Roger Waters' The Wall concert On 21 July 1990, ex-Pink Floyd member Roger Waters staged a gigantic charity concert of his former band's rock extravaganza The Wall to commemorate the end of the division between East and West Germany. The concert took place at Potsdamer Platz – specifically an area of the former no man's land just to the north of the Reich Chancellery site, and featured many guest superstars. It was preparations for this concert, rather than historical interest, that brought about the first detailed post-Cold War survey of the area with a view to determining what, if anything, was left of Hitler's bunker and any other underground installations. Although sections of the main Führerbunker were found, partially destroyed or filled in, another bunker complex was found further north that even the East German authorities had apparently missed, plus other cavities beneath land bordering the east side of Ebertstraße, although these turned out to be underground garages belonging to a former SS accommodation block. Routes through Potsdamer Platz after reunification After major refurbishment, the S-Bahn line and station reopened on 1 March 1992, followed by the U-Bahn on 13 November 1993. An additional station on the U-Bahn, called Mendelssohn-Bartholdy-Park, was opened immediately north of the Landwehrkanal on 1 October 1998. A new U-Bahn station has also been built at Potsdamer Platz itself, although a decision is still pending on whether to proceed with completion of the line passing through it; in the meantime the station area serves as an impromptu art gallery and exhibition space. A new underground main-line station or Regionalbahnhof (Bahnhof Potsdamer Platz) has also been constructed, opened on 26 July 2006. There are also plans to reintroduce trams to Potsdamer Platz. In addition, many bus routes pass through the platz, while for people with their own cars there are some 5,000 parking spaces, 3,500 of which are underground. The annual Berlin Marathon, which takes place in the last weekend of September, was first held in 1974 but due to the division of