Occurring on the 28th day of Highbleak, Moonsummit was the Long Bleak solstice of the Common Calendar and the shortest day of the year. For much of Commona, the sun was visible for only 8 hours during Moonsummit, with 16 hours of visible moonlight. Many festivals, holidays, and religious observances occurred during this period, especially dedicated towards Telyth and Umori.
Moonsummit was contrasted by Sunsummit, the longest day of the year.