John Muir was born in Scotland on April 21, 1838. His family moved to Wisconsin when he was eleven. Even as a child, he was fascinated by the natural world. He spent hours studying plants and insects. As an adult, Muir walked over a thousand miles from Indiana to Florida. He then traveled to California and discovered the Sierra Nevada mountains. The towering sequoia trees amazed him. Some were over two thousand years old. Muir noticed that logging companies were cutting down ancient forests. Sheep were grazing in mountain meadows and destroying wildflowers. He worried these wild places would disappear forever. Muir started writing articles for newspapers and magazines. His words helped people understand why nature needed protection. In 1903, he went camping with President Theodore Roosevelt in Yosemite. The two men slept under the stars for three nights. Roosevelt was so moved by the experience that he expanded conservation efforts across the country. Muir helped create Yosemite, Sequoia, and other national parks. Today, the National Park Service protects over eighty million acres of wilderness.