December 11 marks International Mountain Day, a day to recognize the majesty and natural beauty of these awesome landmarks, and also to share the important role mountains play in our own lives and the lives of those around the world. Healthy mountain ecosystems are watersheds for the fresh water of over half the world’s population, provide food and renewable resources to countless populations and are home to unique, vibrant ecosystems. We may not be able to move mountains, but increasingly we are chipping away at their long-term health through over-development, mining and deforestation. Help create awareness of their crucial role: if you've visited one of the many UNESCO Mountains, update your TIG profile and let everyone know, and upload your favourite art and photographs to our Global Gallery.