The John Muir Trust has now lodged a petition to the Court of Session asking for a judicial review of the decision in June by Energy Minister Fergus Ewing to grant consent to the 67-turbine Stronelairg wind farm in the Monadhliath Mountains between the A9 and Loch Ness.
When granting approval Mr Ewing had said it would help "keep the lights on across our islands at a time where there is an increasingly tight gap between electricity supply and demand". But John Hutchison, chairman of the John Muir Trust (JMT) said: "It was opposed by both the government's own advisory body on nature and landscape, SNH, and by the Cairngorms National Park Authority."
Because of the scale of the development and opposition, it should have been the subject of a Public Local Inquiry, he said, and therefore in the absence of "proper democratic scrutiny" the JMT had to act.
Meanwhile a public inquiry into a 24 turbine wind farm in Caithness, will test ministers' commitment to protecting wild land, the JMT claim. Limekiln's highest turbines at 456ft would be twice the size of Edinburgh's Scott Monument to blade tip, while the 2,718 acre site, is equivalent to 1,500 football pitches, less than two miles south west of Dounreay. and close to one of Scotland's 42 new Wild Land Areas.
The final map of Scotland's wildest land was published in June, to help the planning process ensure there are no inappropriate developments there.
The JMT says The Limekiln wind farm would visually affect 15 per cent of East Halladale Flows Wild Land Area.
Developers Infinergy say they varied the heights of turbines that could power 40,200 households.