Cheap is a relative word when talking about the Bahamas. That being said, it's my experience that the least expensive airfares, are available by flying into Nassau. More flights, and more carriers servicing Nassau.
The mile is an English unit of length of linear measure equal to 5,280 feet, or 1,760 yards, and standardised as exactly 1,609.344 metres by international agreement in 1959.
Miles : A mile is a most popular measurement unit of length, equal to most commonly 5,280 feet (1,760 yards, or about 1,609 meters). The mile of 5,280 feet is called land mile or the statute mile to distinguish it from the nautical mile (1,852 meters, about 6,076.1 feet).