The Utes and their ancestors migrated into South Park annually, arriving in the spring and staying into late fall. They traveled a regular circuit, following the large game herds until the mountain seeds and berries ripened. During the winter, they gathered as large family groups in protected areas, where they held celebrations that included weddings and sacred rituals. In spring, they again separated into small groups and set out to collect food for the year. As the Utes acquired horses, they began to trade and to expand their territory. Groups banded together under leaders who directed camp movements, hunts, raids, and war parties. In South Park, the Utes coexisted with the early explorers, trappers, and mountain men. The discovery of gold in 1859 brought territorial conflicts. Today, the Ute Mountain Utes and the Southern Utes hold the only reservation lands in Colorado, in the southwest corner of the state.