7th and Last Day of The Feast of Unleavened Bread (Yom Tov)
The 7th and last day of the Feast of Unleavened Bread (Pesah) is the 21st day of the 1st month of Abib/Nissan. This is considered a convocation day and a Sabbath day therefore no servile work is done on this day. This the traditional celebration of the crossing of the Red Sea (Biblical Feasts, 2016).
Reference: The Biblical Feast Days. Retrieved on Feb. 29, 2016. http://biblelight.net/feasts.html