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Mt. Si Relay

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.

For detailed relay information, see our Relay page.


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.

Categories are Open (under 40) and Masters (40+), for both men and women.

For detailed ultra information, see our Ultras page.


New this year, the 25K course is a good option for those that want to run the race but not do a full ultra distance. The trail is generally smooth without too much elevation, with very good support on the course.

For 25K participants, there are 2 full aid stations along the course and a water station at the turn around point.

Categories are Open (under 40) and Masters (40+) for both men and women.

For detailed 25K information, visit our 25K page.

Packet Pickup

Packet pickup will be Saturday, April 22, from noon to 4 p.m. at Everyday Athlete,
11829 98th Ave. NE, Kirkland, WA 98034. 425-821-4301

Packets will include race shirts, numbers and pins.

To limit paper waste, packets will NOT include driving directions, printed course descriptions, maps etc. We encourage runners to print necessary information from this website.

NOTE: Runners not showing up will forfeit their entry fees and shirts. Packet pickup is also available on race day near the starting line. Please arrive early if you choose this option.

Finish line

Refreshments will be available at the finish area. A limited number of shirts from this year and previous years will be for sale.

Results and awards

Results will be available as soon as possible after the race on this website's results page. Awards will be given to the top finishers in each category/division. All ultra finishers receive a unique Mt. Si Ultra medal. Awards not picked up at the event will be mailed. Direct any questions to info@mtsirelay.com

Event history

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.

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