Adds massive cargo ships to the game, that function similarly to trains. Also adds deep sea oil, oil platforms, tanker ships, train bridges and other water based content.
I found this mod (https://mods.factorio.com/mod/CanalBuilder) to be quite useful for making land ports and getting in/out of boats since it adds waterfill (lets you extend water from existing water in a 3-tile wide pattern for the cost of 1x explosive) and allows you (as well other vehicles and biters) to slowly swim in shallow water.
