The wheel of the year
Eight festivals. Four are attested in medieval Irish sources, two are solstices, and several of the names are younger than the electric light.
Samhain
The Irish year-end, and the origin of most of what October now sells.
Yule
Midwinter, and the long argument about what Christmas borrowed.
Imbolc
Ewes in milk, and the first credible rumour of spring.
Ostara
The spring equinox, named for a goddess mentioned exactly once.
Beltane
Fire, cattle, and the start of the light half of the year.
Litha
Midsummer, herb-gathering, and the year's longest light.
Lughnasadh
First harvest, assemblies, and games in honour of a foster-mother.
Mabon
The autumn equinox, and a name borrowed from Welsh legend.