TSS Duke of Clarence was a passenger vessel operated jointly by the London and North Western Railway and the Lancashire and Yorkshire Railway (LYR) from 1892 between Fleetwood and northern Irish ports. In 1906 the LYR bought her outright and transferred her to their summer service from Hull to Zeebrugge, returning to the Irish Sea in winter. During the First World War Duke of Clarence served as an armed boarding steamer. She resumed passenger service in 1920, passing through changes of ownership in the reorganisations of Britain's railway companies in the 1920s, until she was scrapped in 1930.