Boise, ID · October

    City of Trees Marathon with a free coach.

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    Hi! City of Trees Marathon is 51 weeks out. What are you aiming for?

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    Your plan in four answers

    City of Trees Marathon has not announced its next date, so we have estimated October. Change the date below once you know it.

    What are you training for?
    How fast are you right now?

    A recent race is the most accurate. No recent race? Give us your easy-run pace instead.

    How many days a week can you run?

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    51 Race dayWeeks until race day Usually held: Each October
    Distances
    Marathon, Half marathon, 10K, 5K
    Terrain
    Flat

    Course

    The City of Trees Marathon course

    All four races start and finish at Boise State University Stadium, with mass starts at 8:00 a.m. for the marathon and half and 8:30 a.m. for the 10K and 5K. The courses use the Boise River Greenbelt, the paved riverside path that links the city's parks along the Boise River, which keeps the profile gentle and the scenery green and gold in October.

    Read the full course notes

    Hydration stations come roughly every two miles (nine on the marathon, six on the half), and the course closes at 2:00 p.m. The organizers note the river can be unpredictable, so sections may shift for flooding or path construction, and the final course maps are posted once permits are approved.

    Terrain
    Flat
    Distances
    Marathon, Half marathon, 10K, 5K
    Weather on race day
    NOAA 1991–2020 normals for the Boise airport show October lows usually falling from about 47 °F to 36 °F through the month and highs from about 73 °F to 56 °F, so the 8:00 a.m. start is usually crisp. Start in a layer you can drop, and drink at the stations even if you do not feel thirsty.

    What to train for

    A flat greenbelt course is built for steady pacing, so center your plan on goal-pace running: long runs of 18 to 20 miles with the last 4 to 6 at marathon pace, plus a weekly tempo of 25 to 40 minutes.

    Run some long runs on paved bike paths so the narrower path, bridges and turns feel familiar.

    Practice fueling every 30 to 40 minutes, since stations are about two miles apart.

    Sample week

    A sample City of Trees Marathon training week

    A week from the middle of the build, about six weeks out. Your plan sets the real distances and paces from your own fitness and adjusts them every week as you train.

    1. Monday
      • Rest, or 20 minutes of mobility
    2. Tuesday Key session
      • Intervals: 5 × 1 mile at 5K to 10K effort, easy jog between
    3. Wednesday
      • Easy run, 6–7 mi
    4. Thursday Key session
      • Goal-pace run, 10 mi with 6 mi at race pace
    5. Friday
      • Recovery run, 4 mi, or cross-train
    6. Saturday Key session
      • Long run, 16–18 mi, the last 4 mi at race pace
    7. Sunday
      • Easy run, 4 mi, then 6 relaxed strides

    Taper

    Tapering for the City of Trees Marathon

    Start the taper two to three weeks before race day. Cut your weekly volume by about a third, then by half in race week, and keep a few short efforts at race pace so your legs stay sharp. The course is flat, so pacing decides the day: rehearse your goal pace in short segments during race week.

    113 athletes joined in the first two weeks of October
    70% came back within their first week

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    Build me a training plan for the City of Trees Marathon in October. I run [distance] a week, [days] days a week, easy pace [pace].

    City of Trees Marathon training questions

    How long should I train for the City of Trees Marathon?

    Most runners give a marathon sixteen to twenty weeks of focused training on top of an existing base. The plan above counts back from your actual race date, so if you have less time than that it builds the best plan the remaining weeks allow rather than pretending you have longer.

    Is the City of Trees Marathon course hilly?

    Flat. All four races start and finish at Boise State University Stadium, with mass starts at 8:00 a.m. for the marathon and half and 8:30 a.m. for the 10K and 5K.

    What is the weather usually like at the City of Trees Marathon?

    NOAA 1991–2020 normals for the Boise airport show October lows usually falling from about 47 °F to 36 °F through the month and highs from about 73 °F to 56 °F, so the 8:00 a.m. start is usually crisp. Start in a layer you can drop, and drink at the stations even if you do not feel thirsty.

    When should I start tapering for the City of Trees Marathon?

    Start the taper two to three weeks before race day. Cut your weekly volume by about a third, then by half in race week, and keep a few short efforts at race pace so your legs stay sharp. The course is flat, so pacing decides the day: rehearse your goal pace in short segments during race week.

    Do I need an account to get a City of Trees Marathon training plan?

    No. The plan above builds in your browser with no account, no email, and no card. Make a free account only if you want to keep it, log your runs against it, and have the coach keep adapting it as your training goes.

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    See you at the start line.

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    Race facts checked against the official site on October 21, 2026. Registration and official details: City of Trees Marathon official site

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