Plenty of mini buses to hire. Price generally is the same from the port as it is within the Casements. I would suggest buying a taxi ticket £3 return from the port and then get a mini bus from inside the Casements who will take you around the sites then drop you back at the top of main street. You can then walk down do your duty free shopping and get your taxi bus back to the port. Great stop. watch the apes.
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