THEY have brought camping to the masses in search of a cheap weekend in the great outdoors.
But Scotland's national parks are now having to deploy extra rangers to deal with an epidemic of abandoned campsites – complete with cut-price supermarket tents, sleeping bags and other equipment – in beauty spots.
Officials in the Loch Lomond and the Trossachs park and the Cairngorms are routinely discovering tents still erected but otherwise deserted by revellers who have gone home without clearing up. Other tents have been set alight and left to smoulder.
In some areas on the shores of Loch Lomond, rangers attempting to get across the responsible camping message have had to be accompanied by police to deter a violent or abusive reaction.
Bridget Jones, the visitor experience manager at Loch Lomond and the Trossachs National Park, said: "This is one of the most significant problems we have had to deal with in the last five years due to these incredibly cheap tents.
"Certainly this year we have had to provide an increased ranger presence in the park.
"This isn't a bit of litter, it's more a form of fly-tipping."
Tents were once an expensive commodity, but cheaper materials have now brought a drastic reduction in prices. Supermarket chain Asda is selling two-man tents for10 and Tesco sells a camping set for 14.99 which includes a two-man tent and two sleeping bags.
The Outdoor Access Code adopted by the Scottish Parliament was aimed at increasing the number of people, particularly from urban areas, visiting the countryside. But it has also led to more so-called "wild camping" in which visitors pitch their tents outside official sites.
One hotspot has become the east shore of Loch Lomond, which every weekend is becoming a temporary home for young males between the ages of 19 and 24 from across the central belt.
Jones said: "From a National Park Authority perspective we want to encourage people to come and enjoy the special qualities here, but it is also our job to reduce the incidents of antisocial behaviour and encourage responsible behaviour that will protect this special part of Scotland."
The park is now considering setting up its own "semi-formal" campsites "where we can provide firewood, compost and toilet facilities while folk can still have the same experience. Then we can actively educate, alongside the police, on appropriate camping."
David Richards, who owns the Immervoulin Caravan and Camping Park in Strathyre within the national park, said every weekend there are tents left behind. "Some of them are not even taken down," he said.
"The problem is much broader in the form of wild camping. People are pitching tents next to the vehicles, tearing up the national park and burning trees all for the sake of not paying a pitching fee."
The Cairngorms National Park Authority (CNPA) said: "There have always been occurrences of inappropriate camping in the Cairngorms National Park, long before the advent of the throwaway tent, but we are seeing some instances of all of the camping equipment being abandoned now as opposed to just litter – which is bad enough.
"The CNPA is working with land managers and ranger services to deal with camping hotspots and to encourage responsible camping."