I have done the research on trains from Vienna to Budapest, taking one in the morning, and one in the evening. I want to know if it is really a good day trip to do if I can only spend one day there. Is it really worth the time?

It would be a long day, but it is certainly doable. When you arrive in Budapest at Kelti station you are on the red metro line which can take you to the center of things. I'd be sure I knew what I wanted to see and how to sequence the day. If you want some specific suggestions please feel free to email me.

aa: Too much for one day. You couldn't do this glorius city justice. Go to Melk (austria) to see the Abbey and take a Danube Cruise to Krem (bring a rented bike with you). Wander the old village and then bike back. Great day.

I agree that as rewarding as visiting Budapest can be, if you only have one day you probably will get more value from a "side trip" within Austria.

I agree with the previous responses. Budapest is such a beautiful city that it would be hard to do it justice in a days time. It should be experienced by day and also by night with a great night view from on top of Gellert Hill.