A fight to stop overhead cables being erected across rural Denbighshire and Conwy is over after opponents conceded.
SP Manweb plans to erect 10.5 miles (17km) of power lines linking Clocaenog wind farm to a substation at Glascoed.
Members of Pylon the Pressure had been campaigning to stop the proposals, which they said would be a “blight on the landscape”.
Campaigner John Mars-Jones said they had been advised the legal case was not strong enough.
The group had argued the scheme would damage the Grade II-listed farm complex of Berain, near Llannefydd, which was the home of Katheryn of Berain – a descendant of Henry VII.
They argued that the cables and 18 pylons on the land would not only be a blight on the landscape but also interfere with farming operations, and so wanted the cables to be laid underground.
In July, UK Energy Secretary Greg Clark approved SP Manweb’s proposal, following a public inquiry into the plans.
The action group had raised funds for a judicial review but a hearing in April ruled Mr Clark had applied the relevant policies when approving the plans.
Mr Mars-Jones, who farms at Berain, sought a second legal opinion on the ruling and now accepts that the fight can be taken no further.
“The advice we received was that our legal case was not strong enough to justify carrying on, so we have to accept that,” he said.
“It is disappointing… but at least we have tried.”