The Beach End buoy and the Cliff Foot buoy in We Didn’t Mean to Go to Sea both mark the limits of Harwich Harbour, but the Beach End buoy is the one that the Swallows notice as they drift out to sea.
… those buoys .. Beach End and Cliff Foot show where the harbour ends and the sea begins” “And you won’t go out beyond them?” said Mother. “No” said Jim (WD3).
One, with a pointed top, was the Beach End buoy. The other, flat-topped, was called Cliff Foot. Roger was told he had earned full marks by remembering that Beach End must be the starboard hand buoy and Cliff Foot the port hand buoy for vessels coming in (WD6).
Other buoys closer in are the Guard buoy (WD6) and the North Shelf buoy (WD6,7).
“Oh John!” gasped Susan. “That was Beach End buoy. We’re out at sea” “Out at sea … the Beach End buoy” (WD8,9)
There were little pictures of buoys on the chart, with letters beside them, “R” or “B” or “B.W. Cheq”. That last he guessed must mean Black and White chequered. The little picture, that made the buoy look like a leprosy flag, and was marked B.W.Cheq showed that clearly enough (WD9)
Later when they see the Beach End buoy .. it meant that things were on their way to being put right (WD26).
There are pictures of the Beach End buoy in (WD8) and Fending off with the Mop in (WD9).