Do cruise ships carry fresh water from ports or process it from surrounding salt water?

Question

Do they fill up when in port or do they process salt water into fresh water and then serve that?

Answer 1

Modern cruise ships have desalination units which make all the fresh water that that the ship needs for swimming pool, laundry, washing etc.
Drinking water is normally loaded into freshwater tanks when the ship is in port although desalinated water is fit for drinking.

Answer 2

They do both. The conversion machinery for salt water to fresh water can only supply a limited amount therefore the fresh water from port.