From the beginning, the WRA centers all had very liberal leave policies, although these were worked out over time and were not identical from center to center. These included daily leave to shop, compete in sports, and participate in cultural affairs in neighboring towns, and recreational leaves to wander or fish in nearby streams, forests, deserts, or mountains. They also included short-term medical and seasonal work leaves. High school and college-age students left for schooling from mid-1942, and from early 1943 residents took permanent leaves. These latter resulted in wartime colonies of Nikkei in Salt Lake City, Denver, Des Moines, St. Louis, and Cleveland. Chicago attracted the largest colony at several thousand. Overall more than 30,000 took permanent leaves from centers well before the government decided to close them. Eventually, between these leaves and the draft the only Nikkei left in the centers were the very young and the Issei, afraid to settle amongst what they feared was a hostile population. The WRA conducted these policies very carefully, vetting both the re-settlers and the communities where they were destined to live. The centers also had very generous visitation policies. People came and went for all kinds of reasons: relatives touching bases, soldiers visiting families, Caucasian allies building legal cases, and neighbors from adjacent camps. No historic concentration camp had such open-door policies.