Soldiers have begun to remove a temporary footbridge which linked the two sides of Workington in the wake of Cumbria's devastating floods.
The Army built Barker's Crossing over the River Derwent after Northside bridge was washed away in November 2009, killing Pc Bill Barker.
It is no longer needed as a permanent bridge has now been completed.
A party of 128 soldiers is expected to take up to three days to remove the bridge in sections.
Barker's Crossing opened 18 days after Workington was split in two by the heaviest rainfall ever recorded in England.
It reconnected both sides of the town following the destruction of other bridges.
Brigadier Bill Aldridge, commander of 42 (North West) Brigade, said: "Barker Crossing was only ever a temporary emergency measure until other bridges could serve the same purpose.
"The Royal Engineers are very proud of the crossing and are pleased to be returning to Cumbria in happier circumstances.
"Extracting the bridge is a relatively complex operation and will mean we have to close Barepot Road for three days to ensure everyone's safety.
"We have been made most welcome and have been glad to be able to use some of the engineering skills we use in Afghanistan to support Cumbria in its time of need."
Pc Barker was directing traffic away from Northside Bridge when it collapsed.
The father-of-four from Egremont fell into the River Derwent, which had been swollen by record rainfall.