USS Althea (SP-218) was a 60-foot motor pleasure boat that served in the United States Navy from 1917 to 1919 and was sunk by ice in 1920.

Althea was built by the Williams-Whittlesey Co. in the Steinway area of Astoria, Queens, New York, in 1907 for James H.

Formally purchased a month after commissioning, she was employed on Great Lakes section patrol and training duties under the 9th Naval District, operating out of Detroit, Michigan, for the rest of World War I and for several months after the war.

Althea was awaiting sale when she was sunk by ice on 18 March 1920.

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