In March 1868 a 29-year-old John Muir stopped a passerby in San Francisco to ask for directions out of town. “Where do you wish to go?” the startled man inquired. “Anywhere that is wild,” said Muir. His journey took him to the Yosemite Valley in California’s Sierra Nevada, which became the spiritual home of Muir’s conservation movement and, under his guidance, the country’s third national park. “John the Baptist,” he wrote, “was not more eager to get all his fellow sinners into the Jordan than I to baptize all of mine in the beauty of God’s mountains.” Today around four million people a year follow their own thirst for the wild to Yosemite. Learn how the photographer composed these images. (© Stephen Wilkes/National Geographic)

In celebration of the 100th anniversary of the National Park Service, the January issue of National Geographic magazine has to raise awareness on the challenges and wonders of parks across the globe.

"Today, parks are more critical than ever to ensure the health and sustainability of our planet," Chris Johns, chief content officer of National Geographic Society, said in a . "We want people to explore and experience the wonder of these protected places with us and through us, and support our efforts to understand and preserve them."

This year's magazine series features stunning day-to-night photographs created by Stephen Wilkes. To create the images, Wilkes shot thousands of photos and digitally melded the best ones to create one time-spanning panorama.

The year-long project will include features made across all platforms: a comprehensive web portal that includes stories, photograph galleries, travel guides, videos, educational resources and the ability to book travel experiences online.