Rudesheim to Loreley


Does anybody know if there are any short boat trips from either Ruedesheim or Assmanshausen to Lorely Rock? I am finding it hard to find any info online. I am confused about trip lengths, times, schedules etc. The few boat ride websites I have found make it hard to read and make out if the boat trips are return trips.

Ideally we will be travelling Monday 4th Aug A.M to Rudesheim (or Assmanshausen) from Frankfurt by train. We would like to do the Niederwald and ski lift chair lift (in either direction) and get on a boat to see the Rhine. Then get the train home again.

They do a 'ring ticket' with boat for the Niederwald but it appears a very short ride. If anybody can direct me to a website or can tell me if they have done a return boat ride from RH or ASM that would be great :)