…which was 18 October, but I was out celebrating. I saw this factoid recently, which for some reason I thoroughly enjoyed:
Alaska is 2½ times bigger than Texas. At low tide, Alaska is three times bigger.

Alaska Day. On 18 October 1867, “ownership” of Alaska was officially transferred from Russia to the United States. The day is an official State holiday, not to be confused with “Seward’s Day”, but the real party is in Sitka.