Economic integration processes such as trade agreements and customs unions have greatly contributed to the growing fluidity of freight flows across borders, notably in Europe and North America. Still, border effects have not disappeared, and they continue to influence the structure of hinterlands and freight distribution. The three most common border effects are:
- Gateway. Locations that are able to handle and process cross-border traffic are pre-defined by customs agencies and are commonly known as ports of entry. The choice of ports of entry can be subject to standard geographical constraints, such as a bridge across a river, or a deliberate choice to reduce costs by operating only a few facilities along a border. Therefore, transport networks are often constrained to use specific gateways (or ports of entry) to go from one jurisdiction to another. This creates a convergence effect on networks and flows where the border represents an opportunity to consolidate or deconsolidate shipments. It also incites the setting of high-capacity corridors, which can reinforce the border convergence effect. While this structure is common in maritime shipping and air transportation, it also occurs at land gateways.
- Barrier. Relates to a conventional border effect where a change in jurisdiction imposes a sudden friction effect. It mostly involves customs procedures, tariffs and duties, delays at border crossings, and also physical differences in transport infrastructures, such as capacity. The border will strongly deter cross-border traffic if the trade regime is substantially different. Rail gauges are an example of capacity change taking place at a border (e.g. between Europe and Russia). Therefore, the border usually marks a change in the efficiency of freight distribution and is related to a different transport rate structure.
- Operational cost differences. As borders mark a change in jurisdiction, those jurisdictions commonly have differences in operational costs such as labor, land value, energy, and taxation levels. This can be linked to different levels of economic development, such as borders between developed and developing countries (e.g., the United States and Mexico) or subsidies and economic development policies (e.g., Europe). In a setting where there are notable operational cost differences, freight distribution activities will tend to locate where operational costs are lower and use the proximity offered by border regions to service jurisdictions having higher operational costs. This can take the form of transloading activities, where cargo units are moved into different loads.