Largest of three sections, the 77km line connects Fort Augustus and Tummel Bridge substations. The new grid substation was opened at Tummel Bridge and the one at Auchterawe, Fort Augustus has been extended.

Completion of the section enables transmission of energy between Beauly and Tummel Bridge substations (127km).

The second line links the UK’s highest transmission tower at the 2,682ft Corrieyairack, and passes through the Drumochter Pass and Highland Perthshire.

Beauly Denny project director Alastair Brand said: "The central section of the project required teams to construct 209 steel towers along the 77km route linking Fort Augustus and Tummel Bridge substations.

"We have had a very good year in terms of progress and are now looking towards the erection of the final tower, in our licensed area, during 2015."

The third section of the 220km Beauly Denny project, which is under construction, is expected to be commissioned in 2015.

The entire project is scheduled to be completed by November next year with the construction and energization of the 30km section linking new substations at Braco and Denny.

The first 50km section connecting Beauly and Fort Augustus substations was completed in July 2013.

Image: The 220km Beauly Denny project is expected to be completed in November, 2015. Photo: courtesy of SSE.