Engineers have started work on replacing a railway bridge damaged by a derailed train.
Eleven wagons overturned when a freight train carrying ballast overturned on the bridge acros the river south of Ely on June 22.The river has been closed to navigation because around 50 tonnes of gravel and other debris were dumped in the channel.
A new road is being built so a 100-tonne crane can reach the scene of the crash. Network Rail says the work could take months.
Booms have been put across the river to trap oil and brake fluid from the wagons.