The Book of Numbers describes the layout of the encampment during Israel’s 40 years of wilderness wanderings (2:1–34). The tribes encamped around the tabernacle, both in order to stay close to the tent of meeting and to defend it during attack. The four sides were surrounded by four groups, led by Judah, Reuben, Ephraim, and Dan. The Levites—specially chosen to be close to God—camped around all sides of the tabernacle.