BT is laying a 70km fibre optic submarine cable between Orkney and the Scottish mainland to help bring its 21st Century Network to the Northern Isles.
The telco has contracted Global Marine Systems to install the cable under the Pentland Firth from Skaill Bay in Orkney to Dunnet Bay near Thurso.
The cable will provide connectivity to the Northern Isles alongside existing microwave radio links.
"This is another major step in the preparatory work we are progressing so that people living in the Northern Isles can share in the benefits that our next-generation network will bring," said Brendan Dick, director of BT Scotland.
BT has also announced further investment to replace equipment in more than 1,000 exchanges across Scotland.
"It is one of the biggest projects BT has ever undertaken and much more work will have to be done before 21CN comes to Orkney and Shetland," Dick added.
"Nearly 60 exchanges in the islands, from the largest to the smallest, will have existing equipment removed and replaced with 21st Century kit.
"And it will be well worth the wait, because every exchange, no matter how remote, will have the same capability as a city centre exchange."
The project follows Global Marine's successful installation in May of a cable system connecting the UK with Guernsey in the Channel Islands.
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