Lake Sammamish Boat Launch
4455 East Lake Sammamish Pkwy SE
Issaquah, WA
Help us raise a MONSTROUS amount of support for local students on October 24th! ISF Monster Mash 5K is a community-based, family-friendly event that raises funds for programs that serve students attending all 27 ISD schools.
We welcome all-ages and abilities. Convenient onsite parking, phased start times, and a professionally chip-timed course ensure a great experience for all. You’ll appreciate the flat, paved, out-and-back route whether you’re setting a new 5K PR or enjoying a brisk walk together as a family! Bring your creativity – festive costumes are encouraged! Downloadable photos are free and all registrants also receive raffle tickets for prizes.
This event sells out every year, so don’t wait to register! Every registration submitted by October 11th receives a 2026 Monster Mash technical race tee & medal. Don’t need/want a shirt? Select the No-Shirt Registration option and more of your race fee will be directed to fund programs for students!
MONSTER MASH 5K SPONSORS
Sara Miller Group – Windermere Real Estate
