<Table> <Tr> <Td> </Td> <Td> This article includes a list of references, but its sources remain unclear because it has insufficient inline citations . Please help to improve this article by introducing more precise citations . (October 2016) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article includes a list of references, but its sources remain unclear because it has insufficient inline citations . Please help to improve this article by introducing more precise citations . (October 2016) (Learn how and when to remove this template message) </Td> </Tr> <Table> <Tr> <Th_colspan="2"> Gulf Coast megaregion </Th> </Tr> <Tr> <Td_colspan="2"> Megaregion </Td> </Tr> <Tr> <Td_colspan="2"> States that border the Gulf of Mexico are shown in red . </Td> </Tr> <Tr> <Td_colspan="2"> Coordinates: 30 ° N 90 ° W ﻿ / ﻿ 30 ° N 90 ° W ﻿ / 30; - 90 Coordinates: 30 ° N 90 ° W ﻿ / ﻿ 30 ° N 90 ° W ﻿ / 30; - 90 </Td> </Tr> <Tr> <Th> Country </Th> <Td> United States </Td> </Tr> <Tr> <Th> States </Th> <Td> Alabama Florida Louisiana Mississippi Texas </Td> </Tr> <Tr> <Th> Principal cities </Th> <Td> Houston New Orleans Tampa </Td> </Tr> <Tr> <Th> Largest city </Th> <Td> Houston </Td> </Tr> <Tr> <Th> Largest metropolitan area </Th> <Td> Greater Houston </Td> </Tr> </Table> <Tr> <Th_colspan="2"> Gulf Coast megaregion </Th> </Tr>

What is the largest urban region in the coastal south
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