The moment the Queen made the first long-distance call
A hi-tech celebration will be held to mark the 50th anniversary of the first long-distance telephone call made without the help of an operator.
The 1958 call was made by the Queen to the Lord Provost of Edinburgh from the central telephone exchange in Bristol.
Telephone engineers involved in the historic event will use latest video-conferencing technology to recreate the call with BT staff in Edinburgh.
BT said the Queen's call was a "major milestone" in UK telecommunications.
The Queen started her call by saying: "This is the Queen speaking from Bristol. Good afternoon, my Lord Provost."
One of the engineers present at the time, Brian Fox, said: "It was one of the most important days ever in telecommunications history and a huge amount of work went into making sure the day went without a hitch."
David Hay, head of heritage at BT Group, said communications technology had moved on at a rapid pace since "those humble beginnings".
"We now live in a world with high-speed internet, digital television and mobile telephony, all of which are taken for granted," he said.
"This anniversary is an opportunity to celebrate the tremendous technological successes achieved in the past and present, which are transforming all of our lives."
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