About Leslie

The day I tried rock climbing inevitably changed my life forever. Before I knew it, I quit my job as a white water canoe trip guide and was road trip bound, set to explore rocks across North America. I went on to travel the world to climb, pushing myself in all disciplines of the sport and eventually became a professional rock climber representing many top companies over the years. Making a return to adventure guiding, I got certified as a PCGI Lead Guide and Mentor and started a guiding company based out of Thornbury, Ontario called On the Rocks Climbing Guides. For over 10 years I ran rock climbing courses and adventures along the Niagara Escarpment and brought the PCGI certification program to Ontario. I hosted many PCGI courses and exams over the years, watching the local guiding community grow. It was 10 incredibly rewarding years of guiding along the Niagara Escarpment. In 2019 I took a step back from rock climbing, and stepped down as a professional climber. In 2020, I sold On the Rocks to Will Gilbert and in 2023 officially retired from guiding and my role as a PCGI mentor. Change is good! I am loving my new career as a Functional Movement Educator and Pilates Teacher. I now own a fully equipped private Pilates Studio in Thornbury called Peak with Pilates. I do still rock climb (for fun) and love it more and more each day :)

Leslie climbs Magnum Opus 5.13d in Lime Kiln Canyon


Founder of On the Rocks Climbing Guides (Owner for 10 years, sold in 2020, retired 2023)
PCGI Mentor/Certification course provider (Retired 2023)
Professional Climber for 12 years (Retired 2020)
Adventure writer
Public speaker

Graduated with honors, Outdoor Adventure Program at Algonquin College 
Certified PCGI Lead Guide
Approved PCGI SPG/TRG Mentor
Wilderness First Responder

Climbing Highlights:
Established most difficult trad/mixed route at Lion's, Head, Ontario: Above the Clouds 5.13a
Established several sport and traditional routes in Ontario ranging from 5.10d-5.13a
Redpointed sport routes up to 5.13d
Redpointed traditional routes up to 5.13b
Onsighted sport routes up to 5.13a
Bouldered up to V10

First Ascents:
Above the Clouds 5.13a (Mixed). Ontario, 2013.
Stratus Fear 5.12d (Trad), Ontario, 2013.
The Ripple Effect 5.12c (sport), Ontario, 2015.
Whoopee Cushion 5.12c (sport), Ontario, 2013.
Scooped 5.12c (trad/mixed variation), Ontario, 2013
Stihl Your Face 5.12a (sport), Ontario, 2011.
Showered with Gifts 5.11d (sport), Ontario 2016.
Weekday Warrior 5.11a (sport), Ontario, 2014.
Sleeping Husky 5.10a (sport), Ontario 2015
If your day ain't going right, go left. 5.5 (sport, multi-pitch), Ontario 2013.
Safety Meeting 5.11c/d (trad), Ontario, 2017
Sea Legs 5.10 (trad), Ontario, 2017
Buggin' Out 5.5 (trad), Ontario 2017
Fortune Teller 5.12b (sport), Ontario 2017
Arrested Development 5.12d/13a (sport), Ontario 2016
Decade 5.11a (sport), Ontario 2017
Shark Week 5.12a/b (sport), Ontario 2018
Georgian Drive 5.11a (sport), Ontario 2018
Ruby Tuesday 5.7 (sport/hanging belay), Ontario 2018

Leslie gets the first ascent of "Above the Clouds" a 5.13a mixed route that towers 45m above Georgian Bay in Lion's Head, Ontario.

Community & Media:
Co-Founder/Organizer of the Beaver Valley Climbing Festival raising over $11,000 for the Ontario Access Coalition 
Regular Contributor to Gripped Magazine and Mountain Life Magazine
Speaker at Multiplicity at WSSF 2017
Speaker at the Pursuits Film Festival 2018
Slideshow presentations and various outdoor climbing courses for the Alpine Club of Canada, Mountain Equipment Coop and several Toronto climbing gyms like Rock Oasis and Boulderz Climbing Center.
Climbing clinic instructor at the Red River Rendezvous, Red Rock Rendezvous and Beaver Valley Climbing Festival, Devils Lake Craggin Classic, Arc'teryx Climbing Academy
Recognized by the Alpine Club of Canada and Ontario Access Coalition for volunteer contributions to Ontario rock climbing.
Retro bolted several local climbs/cliffs
Photos, appearances, articles, advertisement in Gripped Magazine, Mountain Life Magazine, Dead Point Magazine, Rock and Ice & Climbing Magazine + several guide books. 
Guest appearance in The Continuum Project, a film by Chris Alstrin of Alstrin Films
Featured athlete in Road to Wellness Series sponsored by Scandinave Spa Blue Mountain

Leslie onsights Pushing Up Daddies a classic 5.12 at her home crag: Lion's Head, Ontario
Leslie at her home away from home: Joshua Tree, California.

Websites/Social Media:
Instagram: @leslietimmerz

Live the life you love. Love the life you live.