Vienna is my most frequently visited WHS outside Czechia.

Actually, I like more Prague or Budapest, since Vienna lacks the 3rd dimension, - the city core is pretty flat, and also a big river does not contribute too much to the inscribed part in contrast to spectacular 3D centers of Prague and Budapest intersected by a river.

However, the 4th dimension (time) is perfectly and uniquely readable in Vienna. The center is like an onion: winding medieval streets with fragments of early gothic tower houses and hidden jewels like gothic church St. Maria am Gestade are located inside. The late gothic layer is represented by St. Stephen cathedral, which however has the early gothic westwerk - and it is always a feast for me to distinguish the diverse stages of gothic style. Then we have Graben, and baroque appearance of Hofburg, which also has gothic and renaissance layers inside, followed by great 19th Century Ring with Opera, Museums, Parliament, Municipal Hall. The 19/20th layer is represented by grandiose Secession. All this is completed by parks and gardens, the Belvedere castle, and magnificent baroque Karlskirche. Do not miss also nearby non-inscribed parts of Vienna: Nashhmarkt and Hundertwasserhaus.

In contrast to Prague and Budapest, Vienna time-layering was not spoiled by tasteless Communism.

PHOTO - Michaelerplatz as the case study of time-layering: the archeological findings of Roman Vindobona is presented in the middle of the square. the baroque parts of Hofburg with fountains are the eye-catchers. On the opposite site, there is one of my favorite churches in Vienna: St. Michael with sober facade but nice 13th century-gothic interior, and gothic style is readable also on the spire. On the left from the church there is the Looshaus with plain upper facade, designed by Adolf Loos in 1911. This building was criticized to be ornament- and taste-less, but it is an important landmark of modern architecture. According to Adolf Loos "ornament is a crime". It makes an interesting contrast to contemporary Art Nouveau and Secession buildings in Vienna.