VIDEO: Duke's youngest son explains why he is creating a brewery at Arundel Castle and how it will benefit the planet's wildlife

In 2013, visitors to Arundel Castle paid a nominal additional charge to visit a small menagerie known as Philip's Zoo. A decade later and the teenager who created the modest attraction and whose name adorned the sign is now a young man of 26 with a passion and determination to play his part in supporting animals around the globe facing extinction. Such is his commitment, he even admits to a Meerkat tattoo, reflecting his love for the animal which was a key feature of the petting zoo.

Fifty metres from the original zoo was an extraordinary Victorian building - with its vaulted ceiling reminiscent of the famous Barons' Hall in the castle itself - which was constructed to provide the castle with electricity. Phil explained: "That's why it's called the Engine Shed. It had steam powered generators in here. The castle was the first ever domesticated dwelling to have electricity in it."

As commercially generated power supplanted it, the building - just opposite the St Mary's Gate Inn behind the castle wall - was abandoned and left derelict. "It wasn't really used for many years and then it was John Dunlop's stables and I believe it was called the Champion Room because it is where his prized horses stayed. That is where our Tap Room is now located. The Tap Room used to be three stables!