Bogue Sound is a lagoon in the state of North Carolina separating the Bogue Banks, a 21-mile-long (34 km) barrier island, from the mainland. The sound is part of North Carolina's "Crystal Coast", a tourism marketing term that is also used interchangeably with the term "Southern Outer Banks." It is the southwestern-most sound among the interconnected series of sounds along the Outer Banks that starts in the northeast at Currituck Sound.