SAN ANTONIO BAY
SAN ANTONIO BAY. San Antonio Bay, in southwestern Calhoun County (at 28°18' N, 96°44' W), opens onto Espiritu Santo Bay to the east and is protected from the Gulf of Mexico by Matagorda Island. The mouth of the Guadalupe River forms a large delta area on the western bank of the bay. Guadalupe Bay and Hynes Bay are northern extensions of San Antonio Bay. A ship channel has been dredged from the Seadrift area to the Gulf Intracoastal Waterway, which provides the only major shipping access to the bay. The southwestern shoreline of San Antonio Bay is the northeastern boundary of the Aransas National Wildlife Refuge.