Taking the train from Budapest to Vienna. How far is it to a Hop on off stop. Can you walk it when you get to Vienna ?
Sarah is right you'll have to take the U-Bahn into the city. But once there you shouldn't have a problem with getting on one of the hop on/hop offs. Try this website it might help. www.wien.info The hop on/ hop off hits most everything. I was in Vienna last November and the city is pretty big. I did the hop on/hop off to see everything and then combined a U-Bahn and walking to visit places I specifically wanted to visit over the next few days. Have a great time!
Andrea
There are two main train stations in Vienna (and one is under major construction right now, I think) but if memory serves neither one is really walking distance to the inner city. Find out which train station you'll be arriving at (probably Westbahnhof?) and look into a public transit map for the easy-to-use U-Bahn subway system or take a cab.