Castel /kætel/ is the largest parish in Guernsey in terms of area.

Fort Hommet is a fortification on Vazon Bay headland in Castel, Guernsey. It is built on the site of fortifications that date back to 1680 and consists of a Martello tower from 1804, later additions during the Victorian Era, and bunkers and casemates that the Germans constructed during World War II.