Climbing Guides Page

Yosemite National Park guides have decades of experience to lend to your adventure. Yosemite Mountaineering School guides are your ticket to exploring the park's backcountry. We offer rock climbing, hiking, and backpacking during the warmer months and backcountry ski tours in the winter.  Meet our office staff and our climbing guides below. 

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.

Brandon Geis

Brandon joined YMS in April 2012 after living and working in the park for a year.  In the past year, he has enjoyed trail running, hiking, backpacking, rock climbing, skiing, and snow boarding.  Before he came to Yosemite, Brandon earned his B.S. degree in Business Administration with a focus in Marketing at California State University, Fresno.  While attending Fresno State, Brandon ran cross-country and track, and spent many weekends with friends and family in Yosemite.  He loves spending time outdoors and traveling to new places.  He is eager to learn more about rock climbing and see where that will take him next.

Bill Russell

YMS climbing guide since 1993; began guiding in 1983. Veteran of Yosemite big wall first ascents, desert towers and many alpine ascents. Guides in Red Rocks, NV during the winter. Previous Yosemite Search and Rescue Team member. Previous Professional Ski Patrol member.

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.

Scott Stowe

YMS climbing guide since 1995. Part of the "Dream Team" speed wall climbers. Over 70 ascents of El Capitan, including 2 first ascents; Reticent Wall & Every Man For Himself. Climbing since 1984.

Jeff Scheuerell

Yosemite Mountain School climbing guide since 2001. Extensive Yosemite climbing experience, with 30 first ascents. Has been climbing since 1985. 27 years climbing experience. Guided caving in Sequoia National Park for 5 years prior to joining the Yosemite Mountain School. Wilderness First Responder. BS Resource Recreation, with minor in Outdoor Leadership.

Hope Wolf

YMS climbing guide since 2002. APP Certified Ski Patroller. Wilderness EMT certified. Sonora Pass Highway climbing guidebook author. Climbing since 1990. Leave No Trace Trainer Certified.

Chris Ecklund

YMS climbing guide since 2005. Rock and alpine guiding in the Sierra Nevada since 1998. AMGA certified Rock Guide.

Dave Lane

YMS guide since 2006. AMGA Certified Rock Guide. Climbing for 16 years with 6 El Cap ascents, first ascents in the High Sierra and Deserts of the Southern California. AIARE Avalanche instructor. Climbed in Spain, Mexico and Greece.

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.

Lyra Pierotti

Lyra had her first view of the mountains atop the shoulders of the Tahoe Summer Music Festival's tuba player, back when she weighed less than a tuba. This exposure led her to study ecology and pursue rock climbing.  While studying at UC San Diego, she worked as a guide for her university’s outdoor program. She led rock climbing, backpacking, and sea kayaking trips, and also taught field ecology for several San Diego-based outdoor education programs.  Lyra spent a year living in the French Alps, studying geology, climbing, and skiing. Shortly after her return, pining for more mountain adventures, she relocated to the Eastern Sierra. Dropping plans of going back for a masters degree in ecology, she started guiding on Mount Shasta in the summers – and was thus hopelessly hooked. She now calls Yosemite’s cliffs her cubicle walls for the summer, and spends winters guiding mountaineering, rock/alpine and ice climbing in the Sierra Nevada, and occasionally on the high altitude volcanoes of Mexico.  Lyra is an AMGA Certified Rock Guide, an AIARE Level 1 avalanche instructor, and holds a Wilderness First Responder certification.

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.