The cove is not really a cove. The village sits at the southern end of Whitesand Bay, a mile-long arc of pale shell-sand that runs north along the coast from Land's End. Granite cottages climb in terraces up the slope above the beach, mostly nineteenth-century, mostly built for fishermen who knew the difference between a stout wall and a vain one. The road descends from the A30 trunk road for about three hundred yards in a gentle gradient, then drops sharply for another three hundred to the breakwater built in 1908 to protect the remaining fishing fleet. The fleet today is seven boats. In Edwardian times the same bay was the most important seine fishery in Cornwall, with mullet schools so dense that a single haul could land twelve thousand fish. On 3 March 1977 the Sennen seine took 1,200 stone of mullet in one day, the last serious catch of an industry that was already disappearing.

On 8 June 1881 the cable ship Faraday came in close to Sennen Cove and landed the eastern end of a transatlantic telegraph cable known as the Direct American Line. The shore-end terminated in a temporary hut thirty yards west of the Cowloe Rocks, immediately below the village's hevva station, the lookout from which spotters once signalled pilchard shoals to the seine crews. The cable's far end was at Sable Island, off Nova Scotia. The line was operated for a few decades and then superseded. Several modern submarine telecommunications cables still come ashore at Sennen Cove and are routed via buried landlines to a terminating station at Skewjack a few miles inland, where they join cables from neighbouring Porthcurno. The village now has more bandwidth than people. Most of it passes through without anyone noticing.

Sennen produces a working break in almost any conditions short of dead high tide, and is best at a westerly swell with a light easterly wind, which holds the wave up cleanly until it breaks. The cove is more protected from northerlies than Gwenver at the north end of the bay, and at low tide the sand bars create reliable peelers for beginners while the more committed surfers paddle out toward the headland. Long before surfboards arrived, the locals had a different relationship with the cove. The folklorist William Bottrell recorded the story of the Hooper, a supernatural being who appeared as a light in the mist offshore and hooped, a low warning sound, to keep the fishing fleet off the water when bad weather was coming. The Hooper saved lives. He has not been seen for at least a century. The weather forecasts now do his job.

Two pieces of music carry the name of the cove. In the 1920s the pianist and composer Billy Mayerl, then at the height of his career as a syncopated piano star, wrote a tone-poem called Sennen Cove, recorded with the Columbia house symphony orchestra in 1928. Mayerl had probably holidayed in the village. The piece is wistful where his ragtime works are bright, and the seascape is unmistakable in the writing. Sixty years later the Oxford shoegaze band Ride, on their 1990 debut album Nowhere, included a track called Sennen. The track is a shimmering wall of guitar that builds and recedes like a tide. The abstract painter Tony Davie eventually produced 365 paintings of the horizon at Sennen as a project called Sennen: A Moment in Time. Composers, painters, and surfers keep arriving. Most of them never leave entirely.