Carnival and Ball Season
January to Shrove Tuesday (day before Lent)
Venues throughout the city
Website: www.vienneseball.org/calendar.php

Osterklang (Sounds of Easter)
Mid March
Classical music festival featuring international artists.
Theater an der Wien
Website: www.osterklang.at

Vienna City Marathon
Late April or early May
Begins Arbeiterstrandbadstrasse/Wagramerstrasse and ends Heldenplatz
Website: www.vienna-marathon.com

Festwochen Wien (Vienna Festival)
Mid May to mid June
An extravaganza of music, drama and dance.
Venues throughout the city
Website: www.festwochen.at  

Vienna Jazz Festival
Late June to mid July
As its title states - jazz, jazz, and more jazz.
Various venues
Website: www.viennajazz.org

Im Puls Tanz
July to August
International avant-garde dance festival.
ImPulsTanz, 07, Museumstrasse 5/21
Website: www.impulstanz.com

Donauinselfest (Danube Island Festival)
Early September
One of the largest contemporary music festivals in Europe.
Donauinsel
Website: www.donauinselfest.at

Viennale Film Festival
Last two weeks of October
The country's best film festival.
Various cinemas throughout the city
Website: www.viennale.at

Christkindlmarkt (Christmas Market)Mid November to 24 December
Markets selling trinkets, hand-made products, and the ever-important glühwein (mulled wine).
Rathausplatz, Spittleberg Quarter, Freyung (corner of Innerstadt) and throughout the city