The Port of Isla San Marcos is on the waterways listed below.
|Gulf of California||none|
While many waterways are not part of a larger waterway system, there are a some that belong to two waterway systems. For example, the Tennessee River is a natural river tributary in the Mississippi River System while also being connected to the Mobile Bay River System via the Tennessee-Tombigbee Waterway.
|Maps of Mexico: small large|