Urban activities such as retail or manufacturing have spatial locations from which a land use pattern is derived and influenced by the existing urban form and spatial structure. This form is strongly related to the types of activities that can roughly be divided into three major classes:
- Routine activities are occurring regularly and are thus predictable. They involve commuting (residential to industrial/commercial/administrative) and shopping (residential to retailing). The land use pattern generated is thus stable and coherent. Generally, these activities are zonal and links are from areas to areas.
- Institutional activities. Most institutions are located at specific points and generally have links with individuals. This activity system is related to an urban environment where links are occurring irregularly and according to the lifestyle (students, sports, leisure, etc.) or special needs (health).
- Production activities involve a complex network of relationships between firms, such as management, distribution, warehousing, and sub-contracting. This activity system can be linked to a specific urban environment, but also to a region, nation, or even the world. Some activities are strongly linked to the local urban area, while others are far more linked to the global economy. The land use pattern of activity may thus be linked to an external (international) process.
These activity systems underline the importance of linkages between land uses, which involve the mobility of passengers and freight. The results of these linkages are land use patterns. Thus, understanding the relationships an industrial district has with its labor, suppliers, and customers will provide an overview of the land use patterns in an urban area, but also with other urban areas.