HMS Halsham was one of 93 ships of the of inshore minesweepers

Minesweeper (ship)

A minesweeper is a small naval warship designed to counter the threat posed by naval mines. Minesweepers generally detect then neutralize mines in advance of other naval operations.-History:...

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Their names were all chosen from villages ending in -ham. The minesweeper was named after Halsham

Halsham

Halsham is a village and civil parish in the East Riding of Yorkshire, England, in an area known as Holderness. It is situated approximately west of Withernsea town centre and it lies south of the B1362 road....

 in the East Riding of Yorkshire

East Riding of Yorkshire

The East Riding of Yorkshire, or simply East Yorkshire, is a local government district with unitary authority status, and a ceremonial county of England. For ceremonial purposes the county also includes the city of Kingston upon Hull, which is a separate unitary authority...

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She was transferred to the Air Ministry in 1966 and renamed No.5002. Following her transfer to the RCT in 1974 she was renamed Richard George Masters V.C.