Tried to head west on the trail from the Blue Hole trailhead, but a giant Cottonmouth caused us to change our plans. We headed East toward the Winfred Bonner Trail. It was okay. Mostly sidewalk next to a busy road. A few peeks of the river along the trail. The trail to San Gabriel Park was closed because the bridge was wiped out by the Memorial Day flood.
I've run this trail a handful of times with a double jogging stroller and it is a great workout with great scenery. The kids love the animal tracks that cross the trail, and the cliffs are beautiful. If you don't mind going "off road", it's actually 5 miles of trail and path.