I had never been on the Pacific Ocean before. The first time I tied my 12 foot aluminum boat up to a warf at Skidigate in the Queen Charlotte islands. An old timer came up and asked me If I was from the Interior of the Province. I said that I was, thinking he must know me or something like that. He said " Yep I thought so, You tied up to a solid piling. When the tide drops more than 20 feet about an hour from now your boat will be way up in the air unless the line breaks. I thanked him for the lesson and tied up to the float. Lesson learned.