about and has since operated under the name . Beginning with the reconstruction of the department store in 2004, and the biggest underground railway station of Berlin, some buildings were redesigned and new structures built on the square's south-eastern side. Sidewalks were expanded to shrink one of the avenues, a new underground garage was built, and commuter tunnels meant to keep pedestrians off the streets were removed. Between 2005 and 2006, was renovated and later became a branch of the clothing chain, C&A. In 2005, the began work to extend the tram line from to (Alex II). This route was originally to be opened in 2000 but was postponed several times. After further delays caused by the 2006 FIFA World Cup, the route opened on 30 May 2007. In February 2006, the redesign of the walk-in plaza began. The redevelopment plans were provided by the architecture firm Gerkan, Marg and Partners and the Hamburg-based company . The final plans emerged from a design competition launched by the state of Berlin in 2004. However, the paving work was temporarily interrupted a few months after the start of construction by the 2006 FIFA World Cup and all excavation pits had to be provisionally asphalted over. The construction work could only be completed at the end of 2007. The renovation of , the largest Berlin underground station, had been ongoing since the mid-1990s and was finally completed in October 2008. The was given a pavement of yellow granite, bordered by grey mosaic paving around the buildings. Wall AG modernized the 1920s-era underground toilets at a cost of 750,000 euros. The total redesign cost amounted to around 8.7 million euros. On 12 September 2007 the Alexa shopping centre opened. It is located in the immediate vicinity of the , on the site of the old Berlin police headquarters. With a sales area, it is one of the largest shopping centres in Berlin. In May 2007, the Texas property development company Hines began building a six-story commercial building named . The building was built on a plot of , which, according to the plans, closes the square to the east and thus reduces the area of the Platz. The building was opened on 25 March 2009. At the beginning of 2007, the construction company created an underground garage with three levels below the , located between the hotel tower and the building, which cost 25