Earth is constantly changing. However, over the last several decades, human activity has accelerated these changes around the world. Mountains, for example, may seem permanent and unchanging, but they are just as fragile as Earth's other environments. Written according to state and national STEM standards, this book explores the impact that humans have on mountain environments, from the creation of roads and ski slopes to the use of explosives to create mines. Age-appropriate text is supported by full-color photographs, fact boxes, and sidebars.