The first day of winter observances: Calan Gaeaf, celebrations start at sunset of October 31. (Wales)

Calan Gaeaf is the name of the first day of winter in Wales, observed on 1 November. The night before is Nos Galan Gaeaf or Noson Galan Gaeaf, an Ysbrydnos when spirits are abroad. Traditionally, people avoid churchyards, stiles, and crossroads, since spirits are thought to gather there. The term is first recorded in literature as "Kalan Gayaf" in the laws of Hywel Dda.

October 31 is the 304th day of the year in the Gregorian calendar; 61 days remain until the end of the year.

Wales is a country that is part of the United Kingdom. It is bordered by the Irish Sea to the north and west, England to the east, the Bristol Channel to the south, and the Celtic Sea to the south-west. As of 2021, it had a population of 3.2 million. It has a total area of 21,218 square kilometres (8,192 sq mi) and over 2,700 kilometres (1,680 mi) of coastline. It is largely mountainous with its higher peaks in the north and central areas, including Snowdon, its highest summit. The country lies within the north temperate zone and has a changeable, maritime climate. Its capital and largest city is Cardiff.