The Glenfinnan Estate levies the “administrative charge” to check fliers are aware of the law.
However, users questioned the legality of landowners demanding a fee. Experts said the law was unclear.
Maureen Johnston, from Dunoon, who wants to fly her drone there, said: “It is an outrage to charge the public for an aerial view of your land. There is no law supporting this.”
Glenfinnan Estate signs near the viaduct state “No drone flying”, with a phone number to seek permission.
Johnston said: “I first saw this on YouTube, where a link to an American tourist’s post showed the interaction with ‘Alistair’. Sadly the tourist thought it was a bargain.”
Glenfinnan Estate manager Alistair Gibson said the charge covered his time in going to check operators knew the law, such as drones must be kept 50 metres away from people and buildings.
The viaduct, which is used by steam trains similar to the one in the Harry Potter films between April and October, attracts up to five drones and 4,000 people a day.
Gibson said: “It takes me time to speak to people and try to regulate it. I explain it’s an administrative charge to do this, and issue them with a drone receipt – 99.9 per cent are prepared to pay.
“I hope I am looked upon as a responsible land manager.”
Gibson said the income went to the estate and had totalled hundreds of pounds since the start of the year.
The National Trust for Scotland, which owns the nearby Glenfinnan Monument, takes card payments for those without cash, or when Gibson is not available, which it keeps.
The trust has banned drones from several properties, such as Culzean Castle and Newhailes.
Emily Bryce, its operations manager for Glenfinnan, said: “More than 300,000 visitors are coming to Glenfinnan every year and the use of drones is increasingly popular. This needs to be managed so everyone can enjoy their visit in safety.”
Network Rail said drones must not fly over the railway or cross the track.
The Scottish Outdoor Access Code does not cover drones but the National Access Forum, which advises on land access rights, is due to discuss the issue in May.
Martin Sloan, a partner at law firm Brodies, said: “Landowners have the same powers to prevent drone operators from flying from or over their land as they do to prevent hikers traversing it. This is, of course, very little power indeed.”
Retired sheriff Douglas Cusine said: “I don’t think that, as a general rule, the landowner could levy a charge on someone who seeks to exercise rights [responsibly].”
Malcolm Combe, a senior law lecturer at Aberdeen University, said: “The Land Reform (Scotland) Act 2003 gives responsible access to land and there is an (as yet untested in court) argument that photography could come within that. Drones present novel problems though. The code could be refreshed to try to explain how drone use squares with responsible access.”
Jason Rust, legal adviser at Scottish Land & Estates, which represents landowners, said: “Legislation has not fully caught up to deal with the various questions that drone use can pose. Discussions are ongoing about respective rights and responsibilities in terms of the code. We would advocate a considerate and common sense approach.”