Britain's biggest sports retailer, JJB sports, is to open its first European shop by the end of the year. Holland is likely to be the location for the first outlet, based on the retailer's successful superstore format. The company, which this week announced same-store sales for the 22 weeks to July 1 were up seven per cent and group sales up 12 per cent, said the European store would be around 1,500 sq ms in size.