About This Place
Sebastian is a census-designated place (CDP) in Willacy County, Texas, United States. The population was 1,864 at the 2000 census.
Sebastian is located at 26°20′36″N 97°47′36″W / 26.34333°N 97.79333°W / 26.34333; -97.79333 (26.343249, -97.793347).
According to the United States Census Bureau, the CDP has a total area of 1.7 square miles (4.3 km²), all of it land.