I can remember on my childhood hiking holidays in the the Lake District in northern England coming across little piles of carefully placed stones called cairns which would mark the way along the then not so well trodden paths. They were few and far between and I imagine caused little damage to the environment.
However these days there seems to be a bit of a fad for building them here, there and everywhere in the magnificent countryside of Mallorca. There are so many of them on the mountain paths all over the island that the environmental agencies are getting really worried about the amount of damage that the piles of stones cause.
Having banged their heads against brick walls for years trying to stop people building the cairns they are now starting to dismantle piles and piles of piles! Their photos show the before pictures of around 200 cairns in the beautiful Talaia d'Albercutx area near Pollensa.
When demolished, the agents found themselves with around 10 cubic metres of stone which they'll soon be adding to as they continue their work throughout the mountainous regions of the island.
Basically, the problem with so many stone cairns is that they distort the landscape, expose the soil to erosion by wind and water, and alter the ecological balance of protected habitats which would normally protect vegetation and wildlife.
Phew, that's a lot of reasons not to chuck a another stone on a cairn as you pass by.