The fibre broadband plan will deliver services to more than a million people across Scotland over the next four years in a project backed by public and private funds.
Around 400 premises in Buckie, Moray, can now order fibre services and this will rise to more than 5300 as BT engineers complete the local upgrade.
The Digital Scotland Superfast Broadband project is being delivered in two parts, one covering the Highlands and Islands and the other covering the rest of Scotland, with both projects being delivered by BT.
Deputy First Minister Nicola Sturgeon said: "Today marks an important milestone for the people of Buckie, who are the first in Scotland to benefit from this service.
"This is one of the most ambitious broadband infrastructure projects ever to have been undertaken and will see 95% of premises in Scotland covered by 2017/18."
The project will see BT install more than 500 miles of new fibre cable on land, and another 250 miles of subsea cables connecting the island communities.
Brendan Dick, director of BT Scotland, said: "Taking fibre broadband to the Highlands and Islands is the most challenging project BT is tackling in the UK. It's a massive operation."