Hernals (Viennese German: Hernois) is the 17th district of Vienna, Austria (German: 17. Bezirk, Hernals). Hernals is in northwest Vienna. The district of Hernals stretches out along the canals of the Als River west of Vienna between the Wienerwald (Vienna Forest) and the Gürtel (a main street around inner Vienna).
The Als is the second-longest stream (the longest is the Wien River) to flow from the Wienerwald into the Danube. The highest point, at 464 meters, is Heuberg. The original Vororte of Hernals, Dornbach, and Neuwaldegg were annexed in 1892 and form the heart of the 17th district. The houses in the central areas were built around the turn of the 19th–20th centuries during the Gründerzeit. Further out, the original farmer houses remain, often with gardens and villas added on.
The most notable artists of Hernals are the composers Johann and Josef Schrammel, the actors Josef Meinrad and Ewald Balser, the poet Ferdinand Sauter, the writer Frederic Morton, the church musician Josef Venantius von Wöss, the operetta composer Edmund Eysler, and actress Marianne Schönauer. Furthermore, the architect Friedrich von Schmidt, figure skater Ferdinand Sauter, and the entrepreneur Josef Manner (chocolate) also lived in Hernals.