One of the biggest engineering projects in the UK was officially opened 25 years ago today.

The Channel Tunnel, running from Folkestone to near Calais in France, took more than five years to complete and is now used by 22 million passengers every year.

The deal to build the 31.35 mile rail tunnel had been agreed by then Prime Minister Margaret Thatcher and construction begun in 1988.

KMTV's Kristina Curtis has been speaking to staff about the anniversary

John Keefe, director of public affairs at Eurotunnel, said: "It’s been a quarter of a century of enormous achievement, we’ve transformed this company from basically a work site with a hole in the ground to being the vital link that connects the UK to continental Europe with a route for 25% of all the UK’s trade with the continent and the route for people going on holiday."

However, not everybody believed that the tunnel would ever actually become a reality.

He continued: "You can go 200 years into our past and look at the reasons why the engineering wasn’t there or the transport system wasn’t quite right for an underwater tunnel.

"It took a combination of political will, financial determination and engineering skill to come together in the 1980s.

"We always believed that it was going to be a huge success."

Staff have also been joining in with celebrations, including former member Robert 'Graham' Fagg who actually did the break through at the tunnel on December 1, 1990.

Mr Fagg said: "I actually drove the machine that dug the service tunnel from Shakespeare Cliff towards France.

"I obviously knew the breakthrough was going to happen but I didn’t, for the life of me, expect it was going to be me they called me to the office and they said you are doing the break through tomorrow and I went oh, okay I’ll go along with it. It was a sleepless night!

"You're part of history but you’re only a very small part at that time."

Current members of Eurotunnel staff have also been reflecting their time at Eurotunnel, including Eileen Mellis who works in Transport Control Centre and started three months before the official opening.

"When I started, it was still a building site here," she said.

"Things have evolved so much over the last 25 years, it’s completely different everything changed now.

"There's fun stuff and there's more serious stuff which gives it a good balance. So we can be really quiet sometimes with everything flowing smoothly or we can be really up against it and it can be quite stressful, but its part of the job."

She continued: "We’re like a big family, I'm very happy to still be here and now we’ve got the next generation working here as well."

"We're evolving all the time, I’m really excited to see where the next 25 years sees us..." - John Keefe, Eurotunnel

However, there has been some complications over the years in particular with migration in 2015.

Mr Keefe said: "There was a period of time, when migration was an issue.

"It reached a level where there was a constant flow of migrants trying to get into trucks, the tunnel and the trains but we took a major investment step then.

"We built fences, added cameras and security personnel and created a deterrent where it is so difficult for anyone to get into the terminal that shouldn’t be there.

"The migration problem then moved away from us."

And of course Brexit has been taking a toll on the Eurotunnel too.

Mr Keefe continued: "We took a view very early on that it could be a big issue and so we had to be ready, our customers need us to be ready no matter the outcome.

"We worked very closely with government on both sides, to work out what they needed.

"We set out to be ready on March 29th and we were, it turns out that’s €15 million we’ve invested that hasn’t needed to be used yet but we’re not at the end of the line, we are absolutely ready to go no matter when Brexit happens, not matter what form it takes.

"Our tunnel will run just as smoothly as it always has."

Bosses at Eurotunnel told KMTV earlier this year they are prepared for Brexit

As for the next 25 years, what can be expected to be seen for the Eurotunnel?

"The 25 years we’ve just been through are only the start," said Mr Keefe.

"Our concession to run this lasts until 2086 so we’ve got a massive future ahead of us and still lots more to develop and build and much more traffic to carry.

"The plans for the future are to keep getting bigger.

"It’s a fantastic engineering achievement, it links industries economies, people and it’s become part of our everyday lives. People love the Channel Tunnel."

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