Western Isles, Shetland and Orkney councils have backed a campaign on social media that criticises the cost of air fares to Scottish islands.
Comhairle nan Eilean Siar's leader Angus Campbell said the airline serving the route offered cheaper prices to get to the Algarve than Stornoway.
More than 11,000 people have "liked" the Facebook campaign.
Loganair, which flies the islands routes for Flybe, has defended the pricing structure.
It said children, student, people visiting family members in hospital and islanders were entitled to discounted travel.
Mr Campbell said bringing down the cost of air fares was a priority of Our Islands Our Future, a project seeking more powers for Shetland, Orkney and Western Isles councils.
He said: "A number of islanders have questioned why fares are so high.
"As an example, after a quick look on the Flybe website this afternoon I notice that a flight from Stornoway to Glasgow tomorrow, Wednesday, and returning Thursday would cost a total of £351.
"Just a few days later, the same company is offering a return flight from Aberdeen to Faro in Portugal for just £21 more."
Loganair said that like all commercial transport providers it offered a tiered fare structure and prices were determined by flight, by day and by season.
A spokesperson said: "As is the case with most airlines, fares purchased in close proximity to the time of departure are generally more expensive.
"Loganair is one of the few airlines which continues to offer a 33% discount for children as well as concession fares for students and family members visiting a relative in hospital.
"With the Scottish Government's Air Discount Scheme, island residents benefit from a 40% discount of the fare excluding airport charges and Air Passenger Duty."