Melk to Krems by Bicycle

Yes you can. Look at Nextbike.

We just did this last week. NextBike was fine. However check the bike seat and tires thoroughly before calling to get the unlock code for the bike. Also, leave early in the day. We got the bikes and left Melk about 245, thinking it would be a four hour ride. We biked the Melk side of the river down to the ferry crossing at Spitz. The crossing took nearly an hour which ate up a lot of time, but the bulk of the heurigers seem to be on the side opposite Melk, which we didn't know at the time. We ended up having to stop and catch the bus when it got too dark to continue and we didn't get to visit as many heurigers as we would have liked nor did we get to visit the many castles and cute towns along the way. NextBike has drop offs in most of the towns so you can leave the bike and bus to Krems if the trip is taking too long. We actually drove the route the next day to do some further exploring.

I planned a portion of my recent trip to Austria based on Rick's advice about the Wachau region, including Krems and Melk. We felt a bit disappointed by most of it. We were there in winter, but we spent the night and drove the entire route and stopped in several places. The main road is not particularly picturesque.

Of course you were disappointed, you went there in winter and by car. That is not the way to do it. I wouldn't even think of going to the Wachau in the winter. It is glorious in the spring when the apricot trees are in bloom and when you can spend an afternoon at a heurigen lazing in the sun drinking wine. Bike or boat, not car, is the way to go.

You sure seem to have been disappointed by a lot on your trip to Austria, railrider. Is there anything you liked?

@Emily. I had the same question for @railrider. Personally, I would be happy to be in Austria ANY time of the year, and I don't even ski.