This was the second military post in the area of the Gadsden Purchase (1853).

This highway is well north of the Gadsden Purchase.

After the Gadsden Purchase, Sonora lost more than a quarter of its territory.

Sonora lost more territory in the 1850s, through the Gadsden Purchase.

It is also the largest city in the area of the Gadsden Purchase.

The Arizona section of the border was adjusted in 1853 by the Gadsden Purchase.

During negotiations for the Gadsden Purchase, the issue came up again but transit rights were again denied.

In 1854, another treaty signed here led to the Gadsden Purchase.

Ehrenberg created the first map of the Gadsden Purchase.

On June 8, 1854, the valley became part of the Gadsden Purchase from Mexico.