Hi All,
Just a brief summary of my trip to Melk, Durnstein and Krems, should anyone find it helpful in the future.
The train from Vienna to Melk took about an hour and cost €19. I only booked one-way, as I wanted to stay flexible regarding my time frame and where I returned from. I toured the Abbey and walked around the town for a bit, which I found sweet, but very touristic. What appealed more were the nature trails easily accessible from town, which looked gorgeous, but which I unfortunately didn't have time for.
The cruise lines are about a 10 minute walk from town. There were two to choose from: Brandner and DDSG. They both cost the same and offer a 20% discount to seniors. (Yay!)
The trip down the Danube was the highlight of the day. I got off in Durnstein, about a 1.5 hour trip from Melk, but wanted more time on the river. After speaking with two of DDSG's employees, I learned that I could get off at Durnstein, then get back on the boat when it returned from Krems, back track to Spitz, then cruise back down to Durnstein and Krems. I had no idea that was possible, and was so happy to have the option - which I took. In the end, I spent about 3.5 hours on the river.
Durnstein was sweet, though as someone else pointed out rather small - the historic center is one long block. I had an apricot and chocolate gelato, which was yummy. I found an hour more than enough to spend in town, which was also very touristic.
My favorite town among the three was Krems, which is much larger than Melk and Durnstein. I arrived late, so most of the stores were closed, but loved the town and would have liked spending more time there. I had a wonderful fried chicken and potato salad for dinner (not my usual fare!) at the beer garden, which was cheap and wonderful, and the beer was fresh, cold and tasty! (FMS Steinertor Gastronomie Betriebs (Sudirolerplatz2).
There are a lot of options for getting back to Vienna from Krems. I hopped on the train about 9PM. It was a perfect day.