These are the secrets of the Channel Tunnel as the historic hole turns 30

It is almost 30 years to the day since the opening of the Channel Tunnel – the first to connect Britain to mainland Europe.

After six years of hard work, the longest undersea tunnel in the world opened – and thirty years on, it still helps transport millions of commuters each year from the Strait of Dover to France.

Although plans to build the channel tunnel were suggested as early as 1802, they didn’t come to fruition until the 1980s, when it became the most expensive construction ever proposed at the time.

At its completion, the ‘chunnel’, as it’s become affectionately known, cost £9 billion – equivalent to £22 billion in today’s money.

The construction was not easy – ten workers, eight of them British, were killed in the six year process, which ended in 2024.

Thirty years on from it’s opening, Metro.co.uk has taken a deeper look at the famous tunnel – fun facts, history and specifics.

Surprising beginnings

In 1802, French mining engineer Albert Mathieu-Favier proposed an idea for a tunnel between France and England, lit by oil lamps and even mentioning an artificial island between the channels to ‘change horses’.

Surveys were conducted by both French and British experts to see if a tunnel was feasible throughout the 1800s, but were abandoned over fears the underwater tunnel could be used as an ‘invasion route’.

After years of debate, in 1986 companies Channel Tunnel Group and France–Manche were given rights to the channel tunnel project, and construction began in 1988.

More than 15,000 people were employed during the process, which saw French and British construction crews meet halfway on December 1, 1990.

When the two sides met, they exchanged gifts – the British engineer Graham Fagg gave a plush Paddington Bear to Frenchman Phillippe Cozette. 

The official opening of the Channel Tunnel was on May 6, 1994, and saw French President Francois Mitterrand and Queen Elizabeth II travel towards each other on trains, which stopped ‘nose to nose’ in the tunnel. 

A ceremony was held in Calais, and the tunnel opened to lorries, freights and later cars, trains, coaches and bicycles. 

How big is the channel tunnel?

The tunnel is approximately 32 miles long, stretching from Folkestone to Calais – which means 4827 London buses would fit inside of it.

The tunnel reaches 245 feet below the surface – the equivalent of 107 baguettes balancing on top of each other. 

Made of reinforced concrete, the walls are three feet thick – but believe it or not, the tunnel does actually leak. 

It’s designed to allow water to permeate through (slightly), and is then pumped away. 

Fun facts

In addition to being an amazing engineering feat, the channel tunnel also has some interesting facts. 

Some British workers would travel to France while construction was ongoing to buy cheaper beer, wine and cigarettes.

Most people think the tunnel is just one long tube – but there are three tunnels which make up the ‘chunnel’.

Two are for trains, and one is a smaller service tunnel which can be used in emergencies.

The chunnel has seen plenty of celebrities travel through as well – even the Olympic Torch took a journey through the tunnel on its way to London for the 2012 games. 

Amazingly, the tunnel is also the first landlink between England and France for more than 8,000 years – and thirty years on, still has a life span of more than 90 years left in it.

Sir John Armitt, Chair of the National Infrastructure Commission and a Fellow of the Royal Academy of Engineering, said: ‘The Channel Tunnel is an engineering triumph and a social good.

‘The best infrastructure is the sort we come to take for granted and wonder how we ever coped without it, and the Tunnel has certainly found a place in that category. But it’s salutary to think that it took 30 years from the first agreement between the UK and France to build a tunnel before the eventual scheme opened.

‘The delays were largely due to changes in political will at our side of the Channel and it goes to show the importance of stable policymaking when it comes to building major infrastructure.’

Get in touch with our news team by emailing us at webnews@metro.co.uk.

For more stories like this, check our news page.