Meet Our Guides

Meet Our Guides


Dave Bengston

YMS Director, guide since 1985. AMGA Rock Certified Guide. Leave No Trace Master Certified. Extensive skiing and alpine climbing experience. Big wall guide with 48 ascents of El Capitan, many speed records. Numerous first ascents in Yosemite Valley, Tuolumne Meadows, and Joshua Tree, up to 5.13 and including Kaos, El Capitan. BS Physics.

Josh Helling

YMS guide since 1993. Certified AMGA rock guide, certified PSIA Nordic ski instructor, Rigging For Rescue certified. More than 26 ascents of El Capitan, and 70+ big wall climbs. 1st ascent big wall expedition climbs in Greenland, Baffin Island, Antarctica, Morocco, & Socotra Island Yemen. Many alpine ascents, and ice climbs. Professional photographer, videographer, and film rigger. Active member of Yosemite Search & Rescue.

Nate Kerr

YMS climbing guide since 2007. AMGA Certified Rock Guide. Former Pacific Crest Outward Bound School Instructor, avid climber and backcountry skier, pursuing further AMGA certification. Yosemite Cross-Country ski guide.

Mark Grundon

YMS guide since 2009.  AMGA Certified Rock Guide.  Mark has been climbing for 12 years and has 5 El Cap ascents.  He has guided in Colorado, Alaska, Mexico, and Nepal. Mark is a strong believer in “living the dream”, and following your passions whatever they may be.  He currently guides in El Potrero Chico in Mexico in the winter.  Mark also has an EMT certification, a Leave No Trace Trainer certification, and a B.A. in Recreation and Environmental Studies.

Aaron Jones

Climbing since 2001, in Yosemite since 2003.  Aaron is an AMGA certified Rock Guide. Accomplishments include 40 ascents of El Capitan and over 70+ big wall ascents. Solo ascents of Nose on El Cap in 20 hours and Zodiac route in under 13 hours. Extensive alpine experience including solo ascents of Torres del Paine in Chile.

Miranda Oakley

Miranda has been living, working and playing in Yosemite National Park for six summer seasons. She has worked as a guide for an international outdoor recreation company based in China. She has traveled and climbed extensively throughout the United States, Asia, South and Central America and Spain. She earned a B.A. in International Studies with a focus in Latin America and Spanish Language. Miranda loves the backcountry of the Sierra Nevada and shares her knowledge and enthusiasm for the outdoors with her clients.

Josh McClure

Josh is a certified AMGA rock guide and has been a Yosemite Mountaineering School guide since 2006.  Josh has been climbing for 17 years.  Accomplishments include 30+ ascents of both El Capitan and Half Dome, and more than 100 big wall ascents.  Solo day ascents of The Nose on El Cap 19:30 and the Regular N.W. Face of Half dome 6:00. Day link ups of Half Dome and El Cap 17:20. Josh has extensive alpine experience including ascents of Aconcagua, Fitz Roy, first ascent big wall free climbs and first solo link ups in Patagonia’s Fitz Roy range.  Josh has also climbed and trekked in many of the world’s mountain ranges including, the Himalayas, the Andes, the Atlas, the Pyrenees, the Sierras and the Rockies. Certifications include: B.S. Natural Resources Management, Certified Interpretive Guide through National Association of Interpretation and Current Wilderness First Responder.

Paul Koubek

Paul is a certified AMGA Rock Guide and has also completed the AMGA Alpine Guide course. 8 Ascents of El Cap, including 3 one - day ascents. Former Yosemite Search And Rescue (YOSAR) team member. Began guiding in 1996. Denali Lead Guide (8 summits) also guides on Rainier and Aconcogua. Works for U.S. Antarctic Program as mountaineer and Search And Rescue team member. Graduate: Search And Rescue Institute of New Zealand (SARINZ) vertical rescue training. Has guided and climbed in India, Patagonia, Thailand, Mexico, New Zealand, Canada, Antarctica - significant Antarctic traverse experience (4000+ miles). Wilderness E.M.T. and Leave No Trace Trainer certifications.

Greg Coit

YMS guide since 2011, Greg spends his time backpacking, skiing, and mostly rock climbing with multiple ascents of El Capitan, Half Dome, and walls big and small all across Yosemite and the US. Greg has a bachelors degree in Outdoor Education from the University of New Hampshire; is a graduate from the National Outdoor Leadership School; and has guided rock climbing and backpacking in New England, North Carolina, Washington, and now Yosemite. Greg is a Wilderness First Responder, Leave No Trace Master Educator, and is currently on track to become an AMGA certified rock guide.

Allen Higginbotham

Allen climbed his first Yosemite big wall in 2005. Since then he has made ascends on all Yosemite's major walls, but his main passion is teaching. His dedication to sharing his knowledge and helping new climbers improve their skills, and mentoring skilled climbers, is why he loves working for Yosemite Mountaineering School.