text: I cycled the Danube cycle path this June and mapped the missing part through Enns. I think there were no signs between Enghagen and Ennsdorf, therefore I interpolated with the most logical route - the one from R7. However I believe that in Enghagen there was a sign leading to the ferry (Mauthausen) and and another one towards Enns for a route variant without ferry. 
  
  In the DORIS map it also seems like Upper Austria does route the R1 through Enns: https://www.doris.at/viewer/(S(xzflysl3daxsbkp2mkta10e5))/init.aspx?ks=alk&karte=tourismus&abfragethema=radwege
  