STS059-L15-007 South-Central and Southwestern, Oklahoma, U.S.A. April 1994 Visible in this panoramic, southwest-looking, low-oblique photograph of south-central and southwestern Oklahoma are Oklahoma City (just below center); the east-flowing Canadian River to its south; and still farther south, portions of Lake Texoma and, extending west from the lake, the Red River that separates Oklahoma and Texas. A small portion of the Caprock Escarpment in the Texas panhandle is barely discernible (upper center). The Cimarron River is apparent flowing southeastward to just north of Oklahoma City and arcing northeastward toward Tulsa and the Arkansas River.