The Rotterdam–The Hague metropolitan area (Dutch: Metropoolregio Rotterdam Den Haag)[2] is a metropolitan area encompassing the cities of Rotterdam and The Hague as well as 21 other municipalities.

[1] It is the largest European port, with many international organizations residing within its borders.

Air traffic is supported by Rotterdam-The Hague Airport offering services to a number of European cities, however the majority of air travelers use Amsterdam Airport Schiphol, which is about 45 kilometers from The Hague.

Light rail public transport in the area is offered by RandstadRail, Rotterdam Metro, The Hague tram, and Rotterdam tram, heavy rail public transport is provided by the Dutch railways.

The main reason for the cooperation is economic, to keep and make the area more attractive to international companies and organizations.