Historical clue formulations

• "The ___ Express" (kid-lit classic) — 2025-06-02
• From the Arctic — 2025-05-19
• Like some regions that experience midnight sun — 2023-08-25
• Frigid — 2020-12-10
• Extremely cold — 2019-08-18
• Like some opposites — 2015-12-08
• Word with cap or opposite — 2015-09-15
• ___ vortex (winter weather phenomenon) — 2014-06-09
• Like some opposites — 2014-04-13
• Like one of two extremes — 2013-03-05
• Arctic or Antarctic — 2013-02-18
• Like some bears — 2013-02-12
• Arctic — 2011-02-22
• From the extreme north and south of the earth — 2009-11-02
• Arctic or antarctic — 2009-10-06
• ___ opposites — 2009-06-23
• ___ opposite — 2008-10-19
• Arctic — 2007-06-06
• Like Peary's explorations — 2006-08-21
• Arctic — 2004-10-27
• Like the end of the world — 2004-06-25
• Frigid — 2003-07-19
• Kind of opposite — 2002-10-31
• Like Peary's exploration — 2001-11-06
• Frigid — 2000-11-17
• Kind of cap — 1999-08-15
• Kind of bear — 1997-09-23
• Like 19-Across's expeditions — 1997-03-06
• Like some caps — 1996-04-21
• Frigid — 1995-08-08
• Kind of bear or cap — 1995-07-18
• Kind of extremes — 1995-05-21