http://en.wikipedia.org/wiki/Farne_Islands This is from the 1947 OS map but is more useful than the current OS maps because it uses a lower chart datum and so shows more low tide rocks and reefs.
We hit the mainland just right, just N of Seahouses, nearly paddling into a man in thigh deep water holding hands with his son who was waist deep. We guessed that the beach must be nearby! The foghorn at Seahouses plus the noise of the pleasure boats had given us confidence that we were on track all the way across. The mouth of Seahouses harbour was slightly worrying, we could see all the way across (30m), but not any of the boats we could hear moving. We waited for a pleasure boat to come out of the harbour, then crossed smartly on the basis that an inbound boat would instinctively turn hard to starboard and if we paddled hard ahead we could mange to avoid a collision. A boat came in out of the fog just as we were across. Now all that remained was to find Nacker Hole -not nearly as easy as we had hoped, but eventually we were on land again, and in sunshine. The fog ended at the beach.
We had seen puffins kittiwakes, shags and seals and bits and pieces of the islands. A good reason for a return trip on a clear day.