Historical clue formulations

• German cathedral city, to locals — 2026-01-10
• München : Munich :: ___ : Cologne — 2022-06-20
• Rheinland city — 2020-08-07
• City about 280 miles NW of München — 2020-04-06
• City on der Rhein — 2016-02-05
• City on the Rhine, to locals — 2015-09-21
• City NW of München — 2015-05-12
• Fourth-largest city in Deutschland — 2014-05-08
• Severinsbrücke's city — 2014-02-01
• German cathedral city — 2012-06-18
• Largest city in Nordrhein-Westfalen — 2011-10-08
• ___ Bonn Airport — 2011-06-17
• Rheinland city — 2009-01-04
• 2006 World Cup city — 2007-03-24
• City on the Rhein — 2003-07-31
• City on the Rhine, to locals — 2003-04-28
• City on the Rhein — 2000-07-15
• Rhein port — 1999-01-24
• City on the Rhein — 1997-01-26
• City south of Dusseldorf — 1994-10-30
• Rheinland city — 1994-09-29