Historical clue formulations

• Origami designs thought to bring good fortune — 2021-06-06
• Parts of many an urban skyline — 2020-03-28
• Origami staples — 2013-11-10
• Port sights — 2010-01-17
• Heavy lifters — 2009-12-06
• Common origami creations — 2007-05-06
• Whooping birds — 2005-11-21
• Large weight lifters — 2005-08-06
• Construction site machines — 2005-07-18
• Building machines — 2001-02-26
• Vehicles with booms — 1998-11-03
• Rubbernecks — 1994-04-24