A distinctive quality to Yosemite Guide Service is our extensive knowledge and understanding of the natural history and human events that have shaped Yosemite and the surrounding Sierra Nevada. Our extensive insight of the region provides you a very personal experience, accessing the less crowded destinations to create very special trips & outings. By sharing a life-long connection, expertise, and continual discovery of the Sierra Nevada and Yosemite, our goal is to provide you with an increased awareness and appreciation of one of the world’s most beautiful and inspiring places.
Our Story
Yosemite Guide Service was established to provide high quality nature-based outings to the more common and remote wilderness settings utilizing our unmatched knowledge of the Sierra Nevada and Yosemite. Our focus is on the ecosystem and natural environment that makes Yosemite very unique and extraordinary, developed from an unmatched awareness working for many years as biologists and naturalists in the Sierra Nevada. Combined with an extensive knowledge of the fascinating history of Yosemite and surrounding region, a trip with YGS is intended to create a more personal connection to this amazing environment, and to make each guest feel at home in this spectacular landscape, not just an occasional visitor.
John | Owner, Guide
Owner John Kleinfelter has spent over 30 years living, working, and exploring in the Sierra Nevada. Simply stated, few others can equal the experience and depth of knowledge John has gained as a biologist and naturalist in the Sierra Nevada.
Vivian | Manager, Guide
Born and raised in the Sierra Nevada mountains of California, Vivian is a local self taught wildlife and landscape artist and massage therapist who loves to "host". Vivian partners with John in operating Yosemite Guide Service and the lodgings they offer.
Meet Our Guides
Working for decades as biologists, naturalists, and wilderness instructors in the Sierra Nevada and Yosemite, our guides combine extensive professional knowledge with a friendly, easy going attitude to create extraordinary outings. With inspiring day hikes and distinctive backpacking outings, each trip is individually designed to provide you with an experience you will treasure for years.
Austen | Guide / Manager
Austen Thibault spent his childhood exploring the Sierra Nevada, where he developed a love for nature and outdoor activities like snowboarding and rock climbing. He began his career as a journalist but transitioned to working in the natural world, driven by his passion for the environment. Austen studied ecology and worked for universities, the Forest Service, and nonprofits in field biology before becoming a guide and educator. He is trained in Wilderness First Aid and teaches at an outdoor school for children. Austen's goal is to help people rediscover the wonders of nature and to prioritize safety, fun, and learning as a guide.
Michael | Guide / Manager
Michael Storey has a long and diverse career involving various jobs in Yosemite and the Sierra Nevada. He has guided others on tours and hiking and backpacking trips for the better part of a decade, joining Yosemite Guide Service in 2026. Michael has extensive knowledge of the geology, natural history, native inhabitants, and history of settlement and human development within Yosemite and the surrounding region. With an easygoing but very professional attitude, Michael y shares his considerable knowledge of the Sierra Nevada in a very engaging and inclusive way that makes everyone feel like friends and family. Trained and certified in Wilderness First Aid, his attention to safety and the wellbeing of his guests makes everyone feel confident and comfortable.
Our Mission
Each YGS outing is private and specialized; provided only for the individuals requesting their trip. This is a very unusual style for most guide services. We realize profit can be maximized by adding multiple people to each outing, yet we sacrifice some revenue to make sure you have a very personalized experience. We feel providing you with an exclusive trip is part of our reward, and allows us to focus on sharing our passion and enjoyment for this wonderful place on a very personal level. In a matter of terms, our commitment to you is quality over quantity, and we hope our guests think so, too.
All of our trips are planned and organized upon your request, trying our best to match the dates you want and working with you to create a trip that fits your specific needs and desires. Our goal is to provide the highest quality trip during your visit to Yosemite and the Sierra Nevada, maximizing your vacation time, providing you the best value and unforgettable experience on your trip to Yosemite or exploring the High Sierra wilderness.
By providing individually customized and personalized trips, our focus is centered on delivering exclusive, high quality outings. With great attention to detail and personal service, it is our intent to deliver the most satisfying and personally rewarding outings – just for you and your family, friends, or companions. Just let us know when you’re visiting and what your needs are, and we’ll try our best to make it happen.