Vienna City Hall is the seat of local government of Vienna, located on Rathausplatz in the Innere Stadt district. Constructed from 1872 to 1883 in a Neo-Gothic style according to plans designed by Friedrich von Schmidt, it houses the office of the Mayor of Vienna as well as the chambers of the city council and Vienna Landtag diet.

More details: https://en.wikipedia.org/wiki/Vienna_City_Hall