I believe I was the first one on a bike to ride this new path! First off for the out of area people, this section I'm describing isn't worth a special trip, but it is part of the larger Centennial Trail.
The new path runs from Summit Blvd to near Washington Water Power Station on Post. There are some terrific views of the river and falls along the path.
I was looking for an alternative path for my commute home rather than riding downtown. I accessed the path by riding from Peaceful Valley Park over the river and up the hill to the path. I didn't realize the path was there. I expected to ride on Summit Blvd.
What is nice is this is a nice addition to the Centennial Trail. It is relatively flat and nice pavement. From River Front Park you can ride out through Peaceful Valley Park and only have a short ride on roads to Fish Lake Trail . If you aren't familiar with the ride from Summit Blvd to Riverside via Peace Valley Park it is a paved path, but has a steep short climb. There are numerous single track trails in the area, but I didn't explore those.
Or you can follow the path around to Summit Blvd and then onto Petit Drive.
If anyone has a suggestion on how to get to the top of Sunset Blvd, by the Geiger Post Office, by staying off Sunset Blvd. I'd be interested to hear what you say.