Before that, it looks like the Transfer of the Panama Canal Zone from the United States to Panama would count. Unlikely there was a change in zone, but DST transitions could be different before and after the change. --Ted On 7/17/2013 12:46 PM, lennox@cs.columbia.edu wrote:
On Wednesday, July 17 2013, "Zefram" wrote to "tz@iana.org" saying:
When was the last time sovereignty changed over an appreciable conurbation but not over its entire country? There were some in the resolution of World War II; any later? Any since 1970?
Scanning <http://en.wikipedia.org/wiki/List_of_world_map_changes>, I'd say August 14, 2008 -- the transfer of the Bakassi Peninsula (pop. 150,000 - 300,000) from Nigeria to Cameroon.
Both Nigeria and Cameroon are UTC+1, though.