The TSS Earnslaw has burned Otago coal in her original twin boilers since 1912, making her the southern hemisphere's oldest coal-fired passenger steamship still in commercial service. Built in Dunedin and assembled at Kingston, she was launched to service the high-country sheep stations rimming Lake Wakatipu when road access remained decades away. Her shallow draught and twin screws allowed berthing at improvised jetties, and for sixty years she carried wool bales, livestock, and mail alongside passengers. The shipping route died in the 1970s when sealed highways reached Walter Peak and Glenorchy, but tourism operators recognised the vessel's heritage value and converted her to full-time scenic cruising in 1982. Lake Wakatipu stretches 80 kilometres in a lightning-bolt Z-shape, carved by glacial action during the Pleistocene and today holding New Zealand's third-largest freshwater volume. The lake's distinctive seiche — a rhythmic rise and fall of seven centimetres every five minutes — was explained by Māori legend as the heartbeat of the giant Matau, whose body burned into the lakebed. Modern hydrologists attribute the oscillation to wind-driven pressure differentials and the lake's narrow geometry. The water temperature remains between eight and twelve degrees Celsius year-round due to alpine meltwater inflow from the Dart and Rees rivers, and the average depth exceeds 200 metres. Cecil Peak, Mount Nicholas, and The Remarkables form a continuous alpine amphitheatre above the western and eastern shorelines. Queenstown lake cruises tour the southern basin, typically circumnavigating Queenstown Bay and crossing to Walter Peak Station on the western shore. The TSS Earnslaw's open promenade deck and engine-room viewing gallery allow close observation of the twin steam pistons and original brass fittings. Scenic cruises without farm stops complete the return crossing in ninety minutes, while combination itineraries incorporating Walter Peak's farmyard and homestead extend to three hours. Departures run hourly during peak summer months, scaling back to four daily sailings in winter. Morning voyages benefit from glassier water and sharper mountain reflections, while late-afternoon departures capture alpenglow on The Remarkables' eastern face. Steamer Wharf lies at the foot of Queenstown's commercial centre, a five-minute walk from the Skyline Gondola base terminal.