Historical clue formulations

• Big U.S./Canada falls — 2026-04-20
• Horseshoe Falls setting — 2020-01-22
• Falls for someone who's already married? — 2019-03-24
• Falls on the border — 2015-06-20
• University in Lewiston, N.Y. — 2013-12-01
• Falls for married women? — 2012-06-24
• River flowing between two Great Lakes — 2011-12-23
• Metaphor for a flood of tears — 2010-07-23
• River surrounding Navy Island — 2009-03-14
• Honeymooners' destination — 2009-02-24
• Falls on the border — 2008-06-15
• Relentless flood — 2003-03-30
• Falls on the border — 2003-03-18
• Falls for a lover? — 2002-12-28
• Honeymoon haven — 1999-09-12
• Big honeymoon destination — 1998-12-28
• Western New York county — 1998-07-24
• Horseshoe locale — 1997-11-15
• Lovebirds' destination, maybe — 1994-05-23