May 17 this year is a Christian religious holiday, originally observing the ascent of Christ into heaven on the fortieth day after the Resurrection.
The Christian holiday of Ascension on May 17 is in Sweden celebrated as a so-called "red," free from work day. Known in official Swedish Lutheran Church language as "Christ's Journey to Heaven Day," (Kristi Himmelfärds Dag) the holiday is better known in irreverent vernacular as "Christ the Aviator Day" (Kristi Flygare Dag) by common people. As when holidays occur on Tuesdays, Thursday holidays create what is called a klämdag "pinched in between" day that calls for another day between it and the weekend to be taken off from work - although it counts as one of Swedes five weeks of paid holiday time.
The day before Ascension Day is also de facto considered a half-day holiday.

In olden days Ascension Day was also a first day to go fishing. A big catch on this day signified the coming of a good year. Even earlier, in the eighteenth century, the days leading up to Ascension were used by the local parish and priest to walk the fields to pray for a good harvest. This Catholic tradition was prohibited in 1772.

In general, the religious significance is today oblivious to most people, and little if any significance in church attendance is obvious. However, prior to the four day weekend, attendance is always heavy at the State-run liquor stores, and also grocery stores, where holiday-bound travelers stock up to survive the holiday itself and the Sunday during which some of the shops are closed. Nowadays, many liquor stores are open half or three-quarter days on Saturdays, and unlike times past, fairly strong beer can be purchased at any time in groceries, which remain open until late every evening, holiday or not.