^ Ferries vary. Some of them seem to be in perpetual operation (there's one north of Amsterdam like this, and in the city itself), some are every 90 minutes or so, some stop at 5:30pm in the evening, some only operate during summer season. We were relatively lucky, but my advice would be to do a bit of research. When are you going? I can take a look at our itinerary and see if I can remember any of the ones we used.
^ Ferries vary. Some of them seem to be in perpetual operation (there's one north of Amsterdam like this, and in the city itself), some are every 90 minutes or so, some stop at 5:30pm in the evening, some only operate during summer season. We were relatively lucky, but my advice would be to do a bit of research. When are you going? I can take a look at our itinerary and see if I can remember any of the ones we used.
Mostly free/cheap.