For £22 each you can get a taxi outside the port gates which will take you to all the main sights of Gib and give you a great oversight before dropping you off in the town to do some shopping.
Don't pay the ship's expensive $12 shuttle. there are two different open top bus tours which stop right at the port gates. They range form 15 euro and show you all the sights but then you can get off and on where and when you want.
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