What are some good day trips from Vienna?

I can only speak to the obvious:<BR><BR>Salzburg for sure. Munich if you have a night to spend.

Salzburg - . If you see things in this order (and they are all close together in "Old Town") I think they will make more sense. First the Cathedral and Cathedral Museum, then the Monastery of St. Peter and it's graveyard and catacombs, then the Residenz (of the Prince Archbishops), then Mozart's birthplace and first home.... you will get a good understanding of the flow of the history of the area. From there wander up and down Getreidegasse. You CAN do all that the first day if you push, and it will make things "fall into place" for you Make sure you have some half euro coins in your pocket, there are "info phones" in some of the sites that will give you a good short history of the site. From there just hit the Fodor's guide books and look at some of the other posts on these cities. One thing I will add is that the Nature Museum there is wonderful... but has nothing to do with Salzburg! MAKE SURE you have at least one meal at Stiftskeller St. Peter… it is fabulous!

Certainly Salzburg is great. Another fun trip is to drive down the Danube to Melk abbey and return. Lots of wonderful villages along the way.

I forgot to mention that Budapest is actually closer to Vienna than Salzburg. And Budapest would make another wonderful day trip. Both of these destinations are rather far away, however. For less time traveling and more time visiting interesting places, stick to the immediate area and see Korneuburg, Klosterneuburg, Heiligenkreuz, Gumpoldskirchen, Baden, Bad Voslau, and Wiener Neustadt---all close enough to see in a day.

P.S. I have already been to Salzburg and Munich.

Graz might be a day-trip. The Semmering railroad between Vienna and Graz is said to be scenic and historic. Will know more AFTER early June.

Budapest is worth more than a daytrip and a great city. Bratislava is the capitol of Slovakia and just an hour away. You could see the sites, buy less expensive gifts & crystal and be back in Vienna for a good evening. Krems and wine region & Vienna Woods are nice and you can stop at local cafes/restaurants for the local wine.

I second the choice of the Wachau area of Krems and Durnstein. Very scenic, walking towns, good restaurants.

The Melk Benedictine Abbey is beautiful, well worth the trip from Vienna. My memory on this is a little hazy, but I think it was about a 1 hour train ride.

Melk is truly worth a visit. If you have a car, you can do Melk, Krems and Durnstein in the same day.