Use this calendar for planning purposes only.
Event details subject to change!
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To confirm event status (sold out, cancellations, schedule changes, COVID restrictions, etc.), visit the event website link below.
Mt. Si Relay and Trail Runs
April 27, 2025 @ 8:00 am - 5:00 pm PDT
An event every year that begins at 8:00 am on day last of April, repeating until April 27, 2025
Want to try your first relay race? How about a relay that won’t keep you up all night? The Mt. Si Relay is great for first-timers, as well as for seasoned teams seeking a fun event without too many logistics. There are five people per team, with each team member running two legs of 3-8 miles. Your team of five can ride in one vehicle. Team categories are determined by total team age on race day, which allows flexibility in assembling your team.
Most of the 59-mile course is on the hard-packed Snoqualmie Valley Trail. The trail’s gentle grade is excellent for running with spectacular views. There are ten individual legs, with each team member running two. Exchanges are well-marked and manned by volunteers. Method of exchange is a simple touch off by hand.
As with the relay, the ultra events are excellent venues for runners stepping up to a 50K or 50-mile distance for the first time. The trail is generally smooth without too much elevation, with very good support on the course.
For 50-milers there are six full aid stations and three mini food/water stations. For 50K participants, there are three full aid stations and two mini food/water stations. Of course everything that makes the ultras good for first-timers also makes it a fast and rewarding adventure for experienced ultra runners.
Half Marathon and Marathon
The half marathon and marathon distances are good options for those that want to run the race but do not want to run a full ultra distance. The trail is generally smooth without too much elevation, with very good support on the course.
The event began as the “Falls to Gasworks Relay” in 1983, beginning at Mt. Si High School near Snoqualmie Falls and ending at Gasworks Park in Seattle. In 1999, the event was moved to the Snoqualmie Valley and was renamed the Mt. Si. Relay & Ultra Run. In 1999 the solo run was 52.1 miles, and in 2000 it was changed to a 50.0 miles. In 2003, a 50K solo run was added and the name was changed to Mt. Si Relay & Ultra Runs.
To confirm event status (sold out, cancellations, COVID restrictions, etc.), be sure to visit the event website above.