text: wish the cycle map would put more labels on the contour lines.  no matter, opentopomap to the rescue!
  https://www.opentopomap.org/#map=16/37.90522/-121.73376
  the fact it just kinda ends on the map and cannot be seen in aerials after falling from some 80 metres to under 50 metres, and that aerials showed no evidence where the road followed the stream/valley, does not give me great confidence.
  
  in fact, there had been an intermittent body of water imported where it ends, overlapping today's symphony circle, remembered by https://www.openstreetmap.org/way/82589054/history , long since deleted.  no mapped exit from that water body any time in osm.