The mysterious gothic tower standing above Arundel

Hiorne Tower stands on the high ground of Arundel Park, a solitary, castellated structure whose purpose has never been entirely clear.

Built in the late 18th Century, it carries the name of its architect, Francis Hiorne, who built the structure in the hope of securing a contract to rebuild the local castle.

Martin Alderton, a tour guide and local historian from Arundel Walking Tours, said: "It was a showpiece - it was to say 'look, this is what I can do and this is how I can do it'."

However, the tower, a triangular gothic structure with three turrets, did not win him the job and it remains as a curious monument to his unrealised ambition.

The tower was constructed around 1787–1790, during a period when the 11th Duke of Norfolk was considering a major rebuild of Arundel Castle.

Hiorne, eager to secure the commission, designed the tower as a sort of architectural calling card, a demonstration of his skill in Gothic revival style.

It was built with alternating squares of stone and flint, a design which "would have taken an awful lot of time and effort" if used on the castle said Alderton.

The castle's eventual reconstruction went to others and Hiorne died a poor man.

"He put his whole life into this, all the money that he had," Alderton told Secret Sussex.

It is believed that Hiorne died just two years after the building was completed.

During the 19th Century, it served variously as a lookout, a signalling point, and even temporary accommodation for estate workers.

In the 20th Century it became a landmark for walkers crossing the park, a silent sentinel overlooking the Arun valley.

There are tales of a ghost - a lovelorn woman who died at the tower and appears at the top, dressed in white and sobbing.

Hiorne Tower also found its way into popular culture, as the site was used as a filming location for the BBC's Doctor Who in the 1980s.

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