Mercedes refers to itself as the "Queen City of the Valley" or "La Reina del Valle." It is one of the oldest towns in the Rio Grande Valley. The townsite was first located two miles east of the present site and named Lonsboro by Lon C. Hill, who had been active in bringing St. Louis and New York financiers to the area to look into land and irrigation possibilities. The present site in southern Hidalgo County was part of the Capisallo Ranch, and is named for Mercedes Daz, wife of Porfirio Daz, president of Mexico.
Today, Mercedes is a center for agriculture and varied industries, and it is well known for its custom-made boots. The city's proximity to the Gulf of Mexico and Mexico offer abundant recreational opportunities.
More than 100 native and indigenous shrubs and trees were planted on the Mercedes Civic Center grounds by volunteer Fleet Lentz for Texas' 150th Anniversary. Visitors, as well as school children, often visit the site to see the collection of native plants found in the surrounding four counties. The Center is at 530 E. 2nd St.