SS City of Peking was an iron-hulled steamship built in 1874 by John Roach & Sons for the Pacific Mail Steamship Company. City of Peking and her sister ship City of Tokio were at the time of construction the largest vessels ever built in the United States, and the second largest in the world behind the British leviathan Great Eastern.Like Great Eastern, construction of the two Pacific Mail ships was to be plagued with financial difficulties, which threatened to bankrupt the shipbuilder.