Feasts of the Solstice

This holiday is celebrated twice a year: once during summer solstice, which is the longest day of the year; and once during winter solstice, which is the shortest day of the year. The summer festival is more of a time for carnivals, fairs, and general celebration, while the winter festival (at least in colder climates) is more subdued and is a time for each family to celebrate and give thanks for a (hopefully) good harvest that will sustain them through winter.
Along with the Feasts of the Equinox, these two days are set festival days for all parts of Ayndrinor. While each region and town has its own customs surrounding this celebration, there are some constants that remain the same for all. The summer festival is prime time for carnivals, street fairs, and all-night performances in public squares. The far southern reaches and desert areas tend to flip this around and have the carnivals at night, while they have performances and revelry indoors during the heat of the day.
The winter festival falls at a time when most of Ayndrinor is in the middle of winter and temperatures dropping even further. The far northern reaches are often snowed in and/or experiencing subfreezing temperatures, so the people in those regions spend the day with family going through small rituals to give thanks for having sustenance to last the winter. The southern reaches and desert areas are mild enough during the day that they use this time as an excuse for another carnival and festival, with street performances and general celebration.