I am interested in this excursion on St. Thomas on a Fantasy cruise this fall. I watched a couple of YouTube videos about it and it looks like easy snorkeling with an easy ladder ramp into the water from the catamaran, but someone mentioned that it was a really long walk from the Fantasy to the catamaran. Can anyone tell me how long/strenuous this walk is? I am a senior with two knee replacements and, while I can snorkel and swim forever, long distance walking is not for me. Thanks!