Born in Sheffield, Keith Best settled in York and has died aged 85.

The bridge built for the Japanese by prisoners of war under appalling conditions took two months; Keith's replica, built in Sri Lanka with the use of 500 workers and 35 elephants, took eight months and cost £85,000, equivalent today to over £1.2m.

When filming was ended it was demolished in a matter of seconds.

Returning to Sheffield University after the war, Keith completed his degree and trained as a civil engineer.

Joining Husband's in Sheffield, he was sent by the company to build roads and bridges in Sri Lanka, and it was while he was there that he was asked to build the bridge for the film, to be 425ft long and 50ft above the water.

The film's greatness, apart from its authentic-looking bridge, comes from the conflict it portrays between the PoWs' instinct to sabotage the Japanese war effort and the stance taken by their officer, played by Alec Guinness, who sees the bridge as a symbol of British morale, spirit and dignity in adverse circumstances.

Keith's son, Clive, remembers how his father argued with
Hollywood producer Sam Spiegel to let him build the bridge in the first place.

He said: "Sam Spiegel wanted to build a model to save money, but they managed to convince him to build a life-size bridge. The real bridge eventually was essential to the film's greatness.

"They based it on the Forth Bridge, but had to build it out of wood from the surrounding jungle and then when it was built my dad had to push the button to blow it up.

"They got just one shot at it and the first time the train went across they didn't blow it up because of a mix-up with the cameras.

"The train was derailed at the other end and they had to take months out to get it back on track."

Keith went on to work for a firm of civil engineers in Durham and in 1983 he was made an OBE for building bridges.

He retired to York in 1991 and wrote his memoirs, Best Endeavours, in 1992. In his spare time he loved sailing, his favourite craft being Dragon keelboats.

His wife, Maire – they married in 1947 – died in 2000. The couple are survived by their three children, Sally, Jonathan and Clive, and three grandchildren.