Land use patterns differ between developed and developing countries, especially in urban areas. In developing country cities, the central business district (CBD) is typically found in the city center and contains shops, offices, and administrative buildings, many belonging to multinational companies. Industry zones are located along transportation routes leading away from the CBD, causing high pollution levels. The inner zone is a high-class residential area near the CBD containing colonial homes and new flats. The middle zone is for middle-class homes, though of poorer quality than developed countries. The outer zone is where the majority of the poor population lives in very poor quality, informal housing lacking basic amenities and land rights.