Opened on 16 March 1999 in a former chalk quarry after ten years of building works, the site including car parks occupies 240 acres and has a sales floor area of 154,000 m 2 (1,600,000 ft 2 ) over three levels, making it the fifth-largest shopping centre in the UK (after Westfield London, MetroCentre, Trafford Centre and Westfield Stratford City).