Are There Ships?

yes you need a city near beach and the tehnology is needed too

then build harbor in the city and build transport ship

... question is.. why do you need ship when you can just raise yourself a strip of land to walk across?

The enemy might not have ships.

Ships are a pain in the arse. There aren't many beaches to land on and you can't seem to board or leave a ship next to cliffs. At the moment ships are more or less a waste of time. I hadn't thought about raiding a land bridge out of the water - good idea.

The AI doesnt know how to use ships still that is why its always one GIANT land mass.  This is a problem with several 4X games.  Empire total war and Civ 5 even.

You can make beaches now with terraforming spells.