Mt. Helena trailhead: The trail system in Helena is my favorite thing about this town. The dogs (Washoe on the left, Sage on the right) are big fans too. We moved to a neighborhood we call "Mansion District-adjacent" two years ago and hike Mt. Helena daily. We use this trailhead, at the end of an alley above Holter. I'm not going to pretend to know any of the trail names, but the lower ones that head west toward the water tower are normally not as busy as the upper system and there are lots of open spots for super-fast zoomies.
Also, if you took my backpack and dog leashes from this spot last summer, it's not too late to give them back!