This month's issue of National Geographic Magazine features an amazing feature story by Joel Bourne about the massive redwood trees in Northern California. In addition to the entralling article about these unique towering giants, there are several great videos on the web (many of which feature Petzl's tree climbing equipment), including a 'making-of' the cover shot - 84 images of a 300-foot tree stiched together. There's also a great gallery of photos by photographer Michael Nichols