The different suburbs of Johannesburg are generally categorised by compass direction, as different areas of the city have greatly different personalities. Since Johannesburg is such a large city, there is great variety in the suburbs that comprise it. While the Central Business District and the surrounding areas were formerly highly desired wealthy areas, they have lost their former reputation after migrants took over abandoned buildings, and the crime level rose accordingly. The suburbs to the south of the city are mainly lower-class residential suburbs along with some townships, although most suburbs in the South tend to be extremely large and undistinguished.