Abstract
There are very few successful very large detailed transport models which cover populations of over 8 million people. Those that have been attempted, have not generally been successful. Several reasons for this have been suggested but it may be that 4-stage models simply do not apply. However, the model described in this paper has crashed through the 8 million population barrier. It describes the successful New York, USA transport model which covers 20 million people. It is an Activity Based model and this methodis justified in this paper. Its structure is also discussed, along with operational issues, and model application.