Land use in urban areas varies depending on the zone. The central business district (CBD) has the tallest buildings and is the main area for offices, shops, and work but few residences. It experiences high congestion. The inner city has older high density housing like terraced homes and high rise flats that are sometimes abandoned. Suburbs have lower density housing like detached homes that grew due to improved transportation and wealth. The rural-urban fringe is a mixed use area with industry, business parks, recreational areas, housing, and some remaining farms under development pressure.