Until the Ulverston-Carnforth railway opened in 1857, travellers making their way by coach between Ulverston and Lancaster had no alternative but to cross the sands at the head of Morecambe Bay. It was a treacherous route beset by fogs, quicksands, and rapidly incoming tides, and travellers relied on guides to conduct them safely across.

Cox first visited the Sands in July 1834, and subsequently made many drawings, and several oil paintings, of this subject. This watercolour is one of the most famous and accomplished of them. The lively procession of figures leads the viewer's eye into the landscape, and Cox captures the veils of sea mist and distant rain clouds in exquisitely subtle washes of colour.