By the 1840s, the traffic of stagecoaches and wagon trains on the Santa Fé Trail had reached such a volume that buffalo migration was obstructed, causing great deprivation for the Southern Plains Comanche, Kiowa and Arapaho. Understandably, the Indians retaliated: raids became so frequent that a chain of forts was built to protect the trail. Fort Leavenworth became the centre of operations in the Indian Wars, Fort Dodge protected the key junction where Santa Fé’s ‘wet’ and ‘dry’ routes intersected, and Fort Larned became the base for paying annuities to Indians corralled on reservations. Oklahoma became the repository for many of the eastern tribes from the 1830s, while the Great Sioux reservation in the north was set up in 1868, with extended hunting rights in unorganized Wyoming. In 1869, the Union Pacific Railroad was completed, eclipsing the Santa Fé Trail, and signalling the end game for the Plains Indians.