A four funneled liner is an ocean liner with four funnels. The first liner to have four funnels was the German liner SS Kaiser Wilhelm der Grosse and was considered one of the first superliners.
Among these famous four funneled liners or four-stackers was the ill-fated RMS Titanic, which sank on its maiden voyage on April 15, 1912, after colliding with an iceberg and the RMS Lusitania, which sank in 1915 after being struck by a torpedo from a German submarine. In all, 15 four funneled liners were built between 1897-1922. Four of these liners sank during the world wars, and all others besides Titanic were scrapped.
Of these vessels, Cunard's Mauretania was the fastest and even captured the Blue Ribband, the Atlantic speed record, and retained it for 20 years. However, the popularity of four funneled liners was short-lived as the RMS Windsor Castle, built-in 1922 was the last four-funneled liner ever built. However, two of her funnels were removed in the 1930s. This made RMS Aquitania the last surviving four funneled liner and the only one to survive both world wars.