In 1929 the Seronera Game Sanctuary was established. The sanctuary covers approximately 900 square miles and protects some species around the Seronera area. A park was designed in 1940 that extended from Lake Victoria in the west to Crater Highlands in the east covering 5,500 square miles. In 1950, the Serengeti region was made a closed game reserve and all game hunting was banned. The boundaries were redrawn in 1951 and the Serengeti was established as a national park covering 4,600 square miles.
Increasing demands of the [G 29 / Masai] for grazing land and the needs of wildlife resulted in a realignment of the park's boundaries once again in 1959. The size remained the same but the compositions changed substantially. The eastern plains and Crater Highlands were excised from the park and became part of the Ngorongoro Conservation Unit. The Masai were resettled out of the park and given grazing rights in Ngorongoro.
To compensate for the land loss, the Northern Extension was added to the park and the boundary in the west was extend to protect the animals as they migrated through the Duma region. In 1968, the boundary of the park was extended to the Tanzania-Kenya border making the park 5,700 square miles.
