Shavuot  commemorates the revelation of the Torah on Mt. Sinai to the Jewish people, and occurs on the 50th day after the 49 days of counting the Omer. Shavuot is one of the three biblically based pilgrimage holidays known as the shalosh regalim. It is associated with the grain harvest in the Torah. Here is Shavuot Collection by Netafim 55.