There are a handful of other trails that can link with Stack Rock trail (signed as Freddy’s Stack Rock), but the route mapped here stays on Stack Rock trail the whole way, making a stem and loop that begins from an unofficial trailhead on Bogus Basin Road. The first couple of miles are quality singletrack rolling across panoramic hillsides, through meadows and pockets of forest, with some small-medium rock features. The tread is mostly hardpack and smooth, with just a few sandy sections.

At a multi-trail junction, the track changes character significantly. It becomes wider and flatter, following an old road, and enters deeper forest. A shady and easy pedal soon leads to a fork where both trails are signed “Freddy’s Stack Rock,” making the start of the loop. It’s recommended to go left here, to get the climbing out of the way, and save the better trail for the downhill. The ascent is pretty steep, on an old road that’s rutted in places. At the top of the hill you’ll see the spur trail to Stack Rock, and you won’t want to miss the short detour.

From the base of this huge chunk of granite, you’ll get impressive views over the valley and surrounding mountains. Scramble up one of the outcrops for an even better vantage. Back on the trail, the loop continues beneath the sheer west face of the formation, then turns into excellent singletrack for a swooping descent through leafy montane forest. At another fork, you’ll have the option to switch it up by taking a connector to Mr. Big Trail, or you can continue on Freddy’s Stack Rock to complete the loop as mapped here.

Sources: https://www.ridgetorivers.org/ https://www.cityofboise.org/departments/parks-and-recreation/parks/stack-rock-reserve/