This is Restormel Castle, Lostwithiel - or at least what remains of the building. It played a part in the English Civil War.
It was 1644 and a Parliamentarian army (Roundheads), commanded by the Earl of Essex, had marched into Cornwall but had become trapped between two Royalist armies.
The Parliamentarian Head Quarters was at Lostwithiel and even though the castle had little strategic importance it provided a useful look-out post. There are far views from the top of the castle.
Despite guns being positioned on the chapel roof, and also probably on top of the gatehouse, the castle was easily captured on 21st August, 1644 by Sir Richard Grenville, who found 30 'rebels' and 'divers barrels of beef'.
This was the beginning of the end for the Parliamentarians who were forced to withdraw from Lostwithiel and eventually surrendered at Castle Dore, north of Fowey on 1st of September, 1644.
All in all I enjoyed the visit to Restormel Castle, which was made even better as there was no one else about!
And finally how the inside of the castle may well have looked in the 1600s.