The greater Sabbats

The Greater Sabbats are religious festivals celebrated at more or less equally spaced intervals throughout the year. There are a total of eight Sabbats in the Wiccan calendar, four of which are greater Sabbats, and four are the lesser Sabbats.

The Greater Sabbats are:

Samhain  also known as Halloween or All Hallow's Eve, which is celebrated on October 31st. Celebrated from sundown to sundown as witches begin a new day at sundown. The most important festival of the year for witches as it is the Celtic New Year.

Candlemas also referred to as Imbolc or Brigit's Day, celebrated on February 2nd.
Signifies the beginning of spring, although that may be hard to fathom today as many countries are still covered in snow during February. Candlemas is the Christianised name for this festival with Imbolc being the more common Pagan name.

Beltane also known as May Day is celebrated on May 1st. The second most important holiday of the Pagan year.
Lammas also called Lughnasadh celebrated on August 1st. Traditionally a time of giving as the harvest is upon us and a time to count our blessings.

There are also four lesser sabbats. All four are directly linked to the sun. Midsummer and Midwinter are solstices and the remaining two are the Vernal and Autumnal equinoxes. A solstice is either the longest or shortest day of the year and an equinox is when the day and night are of equal length. There is one shortest day, one longest, and two of equal length in a year which explains why there are four lesser sabbats.