大雷恩河（Rio Grande River）成為德州西南方和墨西哥的邊界線。 The Rio Grande River forms the border between southwest Texas and Mexico.

出處: Corpus Christi and Rio Grande Railway Company, [map showing the proposed railroad between Laredo and Corpus Christi and its connections with Mexico], [1874]. CALL NUMBER: G4031.P3 1873 .B5 RR 393