The Beachy Head lighthouse is below the cliff at sea level (well, its base is). The first lighthouse was to the west of the main cliff, called Belle Tout, on the top of a lower cliff, but it had to be abandoned, and the remaining structure was, last year, hydraulically shifted away from the cliff edge to prevent its loss into the sea.

You may have to wait a bit for an answer from Pete M, as he hasn't posted for some time, but I think he has been sailing larger than yachty things off New Zealand. He used to sail a dinghy in Dover Harbour.

Penny