Empty Underwood Leisure Centre in Newport was turned into a cannabis factory capable of producing A 1.6 million in drugs, trial told AN EMPTY Newport leisure centre was converted into a cannabis factory capable of producing drugs with a street value of around A 1.6 million, a court has heard. It was one of a number of properties across the country being used to grow cannabis in an "extensive and audacious" drugs operation, said to worth several million pounds.