Final answer:
The third "pilgrimage" festival in the Jewish calendar, alongside Pesach and Shavuot, is Sukkot. This festival has historic agricultural significance and has evolved to fit into the religious lives of Jewish people.
Step-by-step explanation:
The three "pilgrimage" festivals in the Jewish calendar are Pesach, Shavuot, and Sukkot. Pesach, or Passover, commemorates the liberation of the Israelites from slavery in Egypt. Shavuot marks the giving of the Torah at Mount Sinai. Sukkot, the festival of huts, is a harvest festival during which Jewish people construct temporary shelters to remember their ancestors' agricultural past and the period of wandering in the desert after the exodus from Egypt. While these festivals have historic agricultural significance, they have been adapted over time to fit the religious and urban lives of the Jewish people. They continue to be significant times of observance in the Jewish tradition, connecting them with their history, community, and faith.