Welcome to the Boise Marathon. The Boise Marathon will offer the summer option for our marathon series. June 21st promises to be one of the longest Boise days. Sunrise is at 6.04 a.m. and while Sunset is scheduled for 9.30 p.m., you know that Boise sun can hang in the sky until late into the evening. We can’t imagine a more perfect day to run our Summer Marathon.