7 nights in sheltered accommodation…
Sukkot (also known as the festival of shelters or feast of booths) commemorates the 40 years that the Hebrew nation wandered through the desert in exile with little food, and gives thanks that there is now bountiful harvest. It is customary to construct a shelter (called a Sukkah) with part of the roof open to the sky. Jews reside in these shelters for seven nights (or at least eat their meals in them).
Picture Sukkah by HRSG, on Flickr
One of my favorite holidays.