Beckett grew up about three miles from the Irish Sea. An inveterate rambler, he often visited the shore or viewed the sea from the inland mountains. Images of strand, sea, and skiffs appear throughout his work.
This excerpt from The Calmative (1946) has a bit of the flavor of Ishmael's musings in Chapter 1:
I went right across the city and came to the sea, having followed the river to its mouth. I kept saying, I'll go back, unbelieving. The boats at anchor in the harbor, tied up to the jetty, seemed no less numerous than usual, as if I knew anything about what was usual. But the quays were deserted and there was no sign or stir of arrival or departure. But all might change from one moment to the next and be transformed like magic before my eyes. Then all the bustle of the people and things of the sea, the masts of the big craft gravely rocking and of the small more jauntily, I insist, and I'd hear the gulls' terrible cry and perhaps the sailors' cry. And I might slip unnoticed aboard a freighter outward bound and get far away and spend far away a few good months, perhaps even a year or two, in the sun, in peace, before I died.