Historical clue formulations

• River through four European capitals — 2025-10-01
• Europe's second-longest river — 2024-08-11
• River through the Black Forest — 2024-07-21
• "Blue" river of waltz — 2024-03-27
• Longest non-Russian river in Europe — 2022-02-08
• River that flows through or beside 10 countries — 2022-02-05
• Inspiration for Johann Strauss II — 2014-10-16
• Vienna's river — 2014-05-05
• View from Budapest — 2013-10-09
• Inn's end — 2011-04-30
• Bratislava's river — 2009-11-29
• It rises in the Black Forest — 2007-08-18
• Waltzer's river — 2004-06-23
• River in a Strauss waltz — 2003-11-03
• River in a Strauss waltz — 2003-07-07
• Strauss subject — 2002-06-15