The St. Joseph Peninsula is located in Gulf County, Florida, in the panhandle of Florida, at coordinates (29°42′55″N85°23′05″W). It is a 15-mile long spit, extending northward from Cape San Blas between the Gulf of Mexico to the west and St. Joseph Bay to the east. It is 6 miles west of Port St. Joe at its closest point. The peninsula is also known as St.