Iceland's timezone

[Paul Eggert]

Thanks for looking up the U of Iceland Almanak.
Here's how I translated what you wrote into tzfile format;
I'll include this in the next set of revisions that I propose to ado.

# Iceland
#
# From Adam David <adam at veda.is> (November 6, 1993):
# The name of the timezone in Iceland for system / mail / news purposes is GMT.
#
# (December 5, 1993):
# This material is paraphrased from the 1988 edition of the University of
# Iceland Almanak.
#
# From January 1st, 1908 the whole of Iceland was standardised at 1 hour
# behind GMT. Previously, local mean solar time was used in different parts
# of Iceland, the almanak had been based on Reykjavik mean solar time which
# was 1 hour and 28 minutes behind GMT.
#
# "first day of winter" referred to [below] means the first day of the 26 weeks
# of winter, according to the old icelandic calendar that dates back to the
# time the norsemen first settled Iceland.  The first day of winter is always
# Saturday, but is not dependent on the Julian or Gregorian calendars.
#
# From Paul Eggert <eggert at twinsun.com> (December 9, 1993):
# The Iceland Almanak, Shanks and Whitman disagree on many points.
# We go with the Almanak, except for two claims from Shanks:
#	1.  In 1968 standard time wasn't switched to GMT until Oct 27;
#		this affects only the time zone name and dst flag.
#	2.  Reykavik was -1:28 from 1837 to 1908, local mean time before that.
#
# Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
Rule	Iceland	1908	only	-	Jan	 1	 0:00	0	S
Rule	Iceland	1917	1918	-	Feb	19	23:00	1:00	D
Rule	Iceland	1917	only	-	Oct	21	 1:00	0	S
Rule	Iceland	1918	only	-	Nov	16	 1:00	0	S
Rule	Iceland	1939	only	-	Apr	29	23:00	1:00	D
Rule	Iceland	1939	only	-	Nov	29	 2:00	0	S
Rule	Iceland	1940	only	-	Feb	25	 2:00	1:00	D
Rule	Iceland	1940	only	-	Nov	 3	 2:00	0	S
Rule	Iceland	1941	only	-	Mar	 2	 1:00s	1:00	D
Rule	Iceland	1941	only	-	Nov	 2	 1:00s	0	S
Rule	Iceland	1942	only	-	Mar	 8	 1:00s	1:00	D
Rule	Iceland	1942	only	-	Oct	25	 1:00s	0	S
# 1943-1946 - first Sunday in March until first Sunday in winter
Rule	Iceland	1943	1946	-	Mar	Sun>=1	 1:00s	1:00	D
Rule	Iceland	1943	1948	-	Oct	Sun>=22	 1:00s	0	S
# 1947-1967 - first Sunday in April until first Sunday in winter
Rule	Iceland	1947	1968	-	Apr	Sun>=1	 1:00s	1:00	D
# 1949 Oct transition delayed by 1 week
Rule	Iceland	1949	only	-	Oct	30	 1:00s	0	S
Rule	Iceland	1950	1966	-	Oct	Sun>=22	 1:00s	0	S
Rule	Iceland	1967	only	-	Oct	29	 1:00s	0	S
# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
Zone Atlantic/Reykjavik	-1:27:24 -	LMT	1837
			-1:28	-	RMT	1908	   # Reykjavik Mean Time
			-1:00	Iceland	I%sT	1968 Oct 27 1:00s
			 0:00	-	GMT