Cape San Blas, Florida April, 1997 The Apalachicola Estuary complex and Cape San Blas can be seen in this east-northeast-looking low oblique view. The Apalachicola Estuary is a shallow coastal plain estuary or coastal lagoon that was formed nearly 10000 years ago. The present barrier island system has been in place for the last 5000 years. Just to the right of the center of the image is Saint Vincent Island, a national Wildlife Refuge that covers an area of 19 sq. miles (49 sq. km). Immediately to the right (east) of Saint Vincent is Saint George Island, a narrow barrier island consisting of numerous beaches, sandy coves, salt marshes, and pine and oak forests. To the left (west) of Saint Vincent Island are Cape San Blas and the Saint Joseph Peninsula. The Saint Joseph Peninsula has numerous white sand beaches, dune formations, and a forested interior. The Gulf of Mexico covers the bottom one-third of the image