Flower Garden Banks National Marine Sanctuary is the only sanctuary located in the Gulf of Mexico. Situated 80 to 125 miles (130 to 200 km) off the coasts of Texas and Louisiana, FGBNMS ranges in depth from 52 to 722 feet (16 to 220 m) and includes thriving shallow-water coral reefs, algal-sponge communities, and deeper mesophotic reefs comprised of black coral, octocoral, and algal nodule habitats. When first designated in 1992, the sanctuary consisted of East Flower Garden Bank (EFGB) and West Flower Garden Bank (WFGB), home to some of the healthiest coral reefs in the Atlantic and Caribbean region. Stetson Bank was added to the sanctuary in 1996. In 2021, portions of 14 more primarily mesophotic banks were added to the sanctuary, expanding the sanctuary in size from 56 to 160 square miles. The 17 reefs and banks that make up FGBNMS are a combination of small underwater mountains, ridges, troughs, and hard-bottom patches perched atop underlying salt domes along the continental shelf to form a chain of protected habitats for ecologically and economically important species (including fish, sea turtles, and manta rays) across the continental shelf in the northwestern Gulf of Mexico.