Vodafone and EE have signed a 10-year deal with Eurotunnel to offer mobile services in the Channel Tunnel, 100 metres below sea level.
Customers of the mobile operators will have access to 2G and 3G services in the North Tunnel (UK to France) from March this year. Eurotunnel has signed equivalent agreements with the French mobile operators, Bouygues Telecom, Orange and SFR.
Eurotunnel has said that although the companies faced a "series of technical challenges" to get the service operational, the quality of communication will be equivalent to a call made in Paris or London.
Both EE and Vodafone intend to bring 4G services in the tunnel in the future.
"We're proud to offer customers a superfast 4G service when they're travelling from the UK into Europe," said EE CTO Fotis Karonis.
"It's another technology first for EE, and it's one that will make a big difference to business workers and people going away on holiday. Being connected is such an important part of travelling now and this will be another route we've covered with 4G, making a huge difference to millions of customers who can now make the most of their journey time."
Approximately 20 million people travel through the Channel Tunnel each year.
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