When you are travelling through Austria and you are in Vienna it is an ideal opportunity to spend a weekend in Budapest. Budapest is easily accessible from the Austrian capital by high speed train from Vienna Meidling Station or Vienna Haupthahnhof.
The train from Vienna to Budapest runs 15 times per day, the last leaving at 19:02 and the fastest train takes 2hrs 30 min. This will get you into Budapest in the evening allowing you to check into your hotel and prepare for a busy day ahead after a restful sleep.
There are many great things to see in Budapest and I would recommend on one of those days that you should visit District 6 to visit St Stephen’s Basilica and Vajdahunyad Castle while of course there are so many other things to see and do your 2 weekend could be filled with sightseeing alone.
Visiting Budapest is also a great place to eat. Everyone thinks of goulash and there are many places where you can get a great plate of the beef stew however other great Hungarian delicacies include csülök (roasted piglet), kolbász (Hungarian Sausage) and csirkepaprikás (Chicken Paprikash) while for the coffee lovers the Cafe and cake scene is huge.
On your return journey the train from Budapest to Vienna leaves from Budapest Keleti Train Station and there are multiple services per day and again takes about 2 hrs 30 min. You can leave on Sunday late afternoon/evening and be back in Vienna to sleep and be refreshed for work/studies the next day.
The fast train to Budapest requires a reservation and I find the website Rail Ninja to be a very easy way to reserve and pay for my rail tickets when travelling round Europe. The thing I like best is that a lot of search engines you will be offered a route changing train a bunch of times. Rail Ninja gives you the most direct and fastest route every time.