Vale Castle stands on the edge of the Vale area of Guernsey, which was once a separate island. The Castle is built on the site of an Iron Age Hill Fort built to protect the channel between the Vale and the main Island of Guernsey. It is uncertain when the original Castle was built - possibly during the early 1400s, but the stonework that exists today was built during the American War of Independence, it was used as much as a refuge as a fortification, although it has all the trappings of a true Castle and very thick walls.

The Castle was strengthened again during the Napoleonic Wars when the Channel Islands were at their most vulnerable; but the Nazis destroyed all of this when they re-used Vale Castle, but little remains of their work either.