Somewhere down the river, rail freight continues to answer London’s almost insatiable appetite for construction raw materials. GB Railfreight has been engaged to provide a new flow into an area where few tourists would find themselves taking a day trip. The freight operator is now delivering bulk loads to Aggregate Industries large load terminal in Purfleet, on the north bank of the River Thames in that part of Essex that very much has its own identity on the eastern fringe of London.