etc.) that if you find yourself caught in one, always swim parallel to the shore , until you get out of it - usually it will only be a few metres; never try to swim against it - you will always lose and exhaust yourself so much in the attempt that drowning becomes a serious risk even for the strongest swimmers. A very basic piece of advice which could save many lives. That said, despite being a pretty good swimmer, the open ocean (in fact, open water in general, where you can't see the bottom) scares me so I've never really gone far enough out to get caught in one. If I actually did, who knows? The problem is that in such situations most tend to instinctively panic and forget what they are supposed to do... Another good piece of advice is to always check a tide calendar/local weather conditions, even if you are just going for a walk on the beach and not planning on going in the water! In Calfornia there generally isn't much of a difference between high and low-tide (maybe 15 to 20 metres), and the sea floor slopes downwards rapidly, so it's usually hard not to notice the (relatively slow) incoming tide and easy to make a run for it, but I've still found myself in the unpleasant situation of having to pick my way along very uneven rocks in ankle- to knee-deep water pressed up against an unclimbable cliff face more than once, when