1. Expansion phase: 1969–1982
First Vienna underground expansion phase from 1969 to 1982
Von HerrMay – Eigenes Werk, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=56111289
2. Expansion phase: 1982–2000
Second Vienna underground expansion phase from 1982 to 2000
Von HerrMay – Eigenes Werk, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=56111396
3. Expansion phase: 2001–2010
Third Vienna underground expansion phase from 2001 to 2010
Von HerrMay – Eigenes Werk, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=56111432
4. Expansion phase: 2010–2023
Fourth Vienna underground expansion phase from 2010 to 2023
Von HerrMay – Eigenes Werk, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=56111453
5. Expansion phase: 2023–2028
Fifth Vienna underground expansion phase from 2023 to 2028
Von HerrMay – Eigenes Werk, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=56111483
Von HerrMay – Eigenes Werk, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=56111509