I love Budapest and went there several times during my long stay in Vienna (it is only three hours by train). So much has already been said in praise of this magnificent city that I would only like to emphasize some sites which gained my speical interest.

I am usually not a great fond of spas but visiting Budapest should certainly include such an experience. Alongside the Danube you find the Rudas Bath which is a beautiful traditional stone bath and the Gellert Bath which is one of the prettiest Jugendstil pieces of architecture I've ever seen. Buda Castle is home to two museums. I would recommend the Hungarian Gallery. Next to it you can visit St Matthew Church which is not only impressive but is practically one of the strangest churches I've ever been to. It has a unique style I saw nowhere else. Across the street there is a marzipan museum in a coffee house where you can also enjoy traditional Hungarian cakes.

On the opposite side of the Danube don't miss the Liszt Music Academy. It is an amazing building and is situated near the best restaurants in town (and just a hundred meters from Andrassy Avenue). At the Hero Square there is the Museum of Arts (not to be confused with the Hungarian Gallery which only houses Hungarian art). Its greatest virtue is its El Greco collection.

Non Unesco sites: the new Holocaust museum is architectonically very interesting and the Sculpture Park is where the Hungarians put removed colossal monuments of Communist Budapest together. Most inspiring.