Port Isabel is a city in Cameron County, Texas, United States. It is part of the Brownsville–Harlingen–Raymondville and the Matamoros–Brownsville metropolitan areas. The population was 5,006 at the 2010 census.The city’s name is given to the Port Isabel Detention Center, 12 miles (19 km) to the northwest next to the Port Isabel-Cameron County Airport. Established as a town after the Mexican War of Independence, Port Isabel became an important cotton-exporting port before the American Civil War. The harbor, town and lighthouse all were fought over and exchanged hands during the Civil War.
In September 1967, Hurricane Beulah caused extensive damage to much of the city. On July 23, 2008, Hurricane Dolly, a category 2 storm, also caused extensive damage to the city. Port Isabel is located in eastern Cameron County at 26°4’25” North, 97°12’48” West (26.073675, -97.213234), on the western side of the south end of Laguna Madre, an estuary of the Gulf of Mexico. The Queen Isabella Causeway crosses Laguna Madre to South Padre Island on the Gulf shore. To the southwest it is 23 miles (37 km) to Brownsville, the Cameron County seat. According to the United States Census Bureau, Port Isabel has a total area of 13.7 square miles (35.4 km2), of which 6.7 square miles (17.4 km2) is land and 6.9 square miles (18.0 km2), or 50.94%, is water.
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