The name almost certainly comes from Old Norse - Sandvatn, "sand water" - a reminder that these waters were a Viking highway long before they became Scottish. The bay was a known stopover for longships running the coast between the Orkneys and the Hebrides, and Pictish remains in the area suggest people had been using the cove far longer still. The naturalist Seton Gordon, walking the dunes in the 1920s, counted dozens of wrecks half-buried in the sand. "All of them are old tragedies," he wrote in his 1935 book Highways and Byways in the West Highlands. "Since the placing of a lighthouse on Cape Wrath just over a hundred years ago, no vessel has been lost here." He suspected Viking longboats lay under the dunes too, waiting their century out.

On January 5th, 1900, a farmer named Alexander Gunn was on the beach searching for a lost sheep when his collie suddenly cringed and howled. On a ledge above the tide line a figure was reclining against the rock face. At first Gunn thought it was a seal. Then he saw the hair - reddish-yellow - the eyes greenish-blue, the body about seven feet long. The story he told 39 years later, to a man named MacDonald Robertson, never changed. He maintained until his death in 1944 that he had seen a mermaid of ravishing beauty. The bothy on the bay - once a cottage, now a refuge for walkers - is said to be haunted by the ghost of a shipwrecked sailor who knocks on the windows in storms. None of which has hurt the bay's reputation. In 2018 the Scottish fiddler Duncan Chisholm released an album called Sandwood that won the Scots Trad Music Awards' album of the year.

About a mile east of the beach, the farmstead of Strathchailleach sits alone in the heather - a mid-19th-century building with no road, no electricity, no neighbours. James MacRory-Smith, known to everyone as Sandy, moved in during 1962 and stayed until 1994, living as a hermit. He painted murals on the interior walls, drank from the burn outside, and walked into Kinlochbervie only when he had to. The cottage is now a bothy maintained by the Mountain Bothies Association. Walkers who shelter there for the night sleep among Sandy's paintings - a kind of accidental gallery in one of the most isolated corners of Britain. The bay itself sits in the Sandwood Estate, owned and managed by the John Muir Trust, which protects the dunes, the loch, and the herd of red deer that still drift through the heather behind the beach.