In Hidalgo County, Alamo is located just southeast of McAllen toward Weslaco along US 83 on the banks of the Rio Grande River near the United States/Mexico border and the Gulf of Mexico.
In 1936 Alamo had 1,018 residents and fifty businesses. During the 1940s and 1950s the town served mainly as a shipping point for vegetables and citrus fruits. The population was 1,944 in 1940 and 3,017 in 1950. In 1990 it was 8,210.
Alamo is part of the McAllen-Edinburg-Mission, Texas metro area.