The NPS Rock Creek Park brochure says that bicycles are restricted to paved trails and are prohibited on dirt trails. I’ve had the Garmin course plotting try and route me on the unpaved trails when I am planning a ride so I have to pin more points to avoid the automatic routing. At lot of times the mapping software just knows these are trails and doesn’t have the information that bicycles are prohibited. I reported that to Google for the Falls Church Park trail from Van Buren St to Gresham Place.
Open Street Maps has parts of a trail between Beach and Military listed as the Western Ridge Trail and also listed as cycles permitted. Is their data wrong, are the labels wrong, or are there paved parts of the Western Ridge Trail up there that bicycles would be allowed on?
Looking at the NPS Rock Creek Park map (http://www.nps.gov/rocr/planyourvisit/upload/ROCRmap1.pdf to download or click on “View Park Map” at http://www.nps.gov/rocr/index.htm), it appears that there are a few short sections of the Western Ridge Trail (highlighted in green on the map) where riding a bike would be permitted like around Pierce Mill (shown as solid lines on the map).