A screenshot captured on April 30, 2017 from the official website of Hurst Castle shows an aerial view of the castle.

LONDON, April 30 (Xinhua) -- It was built as a fortress by King Henry VIII, famed as the English king who had six wives, and was used to guard England as a castle up until World War II.

Now conservation work has started to restore Hurst castle in the English county of Hampshire.

A World War II look-out tower and gun emplacements at the castle, Hurst Castle is at the center of a 1.3-million-U.S.-dollar conservation project by Britain's official cultural custodians, English Heritage.

Hurst Castle was originally built by Henry VIII in the 1540s to guard the narrow western entrance between the Isle of Wight and the mainland, known as the Needles Passage. Henry created what was one of the most advanced artillery fortresses in England.

The castle was used as a prison for eminent 17th century captives, and later strengthened during the 19th and 20th centuries.

Hurst Castle stands at the end of a long, narrow shingle spit that connects it to the Hampshire coast. The Tudor-era fort at its heart still looks much as it did in the 16th century.

Until the 1860s the castle was surrounded by a moat and was approached across a drawbridge to the gatehouse, which is beside the north-west bastion.

A spokesman for English Heritage said: "The project will ensure the historic castle is preserved for future generations to enjoy. Extensive repairs will also include restoration to the searchlight positions and the roofs on top of the castle's 19th century wing batteries.

Roy Porter, English Heritage Properties Curator, said: "Hurst Castle is a fascinating and important site. Its features show us how this strategic spot was defended from invasion from the reign of Henry VIII and in subsequent centuries right up to the Second World War.

"Whether 1940s concrete, or 16th century stonework, English Heritage is committed to the conservation of the historic buildings in our care and is investing significantly in doing so."

Jason Crane, director of Hurst Marine who run the castle on behalf of English Heritage said: "Hurst Castle is a significant British landmark in coastal defense history and one which we should celebrate and preserve. We are delighted that English Heritage has invested in improvement works to the castle to ensure the building remains structurally sound."