Sandsfoot Castle was built to protect the Weymouth Bay anchorage, being placed on cliffs overlooking the waterway, opposite Portland Castle on the other side.; ; Sandsfoot was a blockhouse, intended to defeat enemy ships using a battery of heavy artillery, and had minimal protection against an attack from the land.; It was completed by 1541, run by a captain appointed by the Crown, and cost £3,887 to build.; ; There was probably an early agreement that the nearby village of Wyke Regis had a responsibility to support the castle, and in exchange they came to traditionally enjoy an exemption from taxes and militia duties.; The antiquarian John Leland visited the castle soon after its construction, describing it as "a right goodlie and warlyke castle" with "one open barbican", probably referring to the castle's gun platform.
