Maunsell Sea Forts
The Maunsell Sea Forts were small fortified towers built in the Thames and Mersey estuaries during World War II to help defend the United Kingdom, named after their designer, Guy Maunsell. They were decommissioned in the late 1950s and later used for other activities. One became the Principality of Sealand; boats visit the remaining forts occasionally, and a consortium called Project Redsands is planning to conserve one at Redsand.
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Stephen Turner