Sullivan City is a small city located in Hidalgo County, Texas, United States. It is situated in the Rio Grande Valley and has a population of around 5,718 people. The city is part of the McAllen-Edinburg-Mission Metropolitan Statistical Area. Sullivan City is known for its rich Hispanic culture and agricultural industry, with citrus farming being prominent in the area. The city offers a small-town atmosphere and provides various amenities and services to its residents.