The Castle was built on a strategically important shingle spit close to the deep water channel at the mouth of Southampton Water and for over 400 years acted as an artillery position.
The castle was severely damaged by fire in the reign of Elizabeth I and its repair required the felling of 127 oak trees from the nearby New Forest.
Calshot Naval Air Station opened in 1913, from here in this year First Lord of the Admiralty, Winston Churchill took his first seaplane flight.
Manned during World War I Calshot provided Channel defence and a training base for pilots.
It was renamed RAF Calshot in 1918
Calshot was the venue of the famous Schneider Cup Trophy race in 1929 and 1931 at which one of the servicemen assigned to help with event was Aircraftsman Shaw, better known today as Lawrence of Arabia.
Calshot played an important role in the Second World War and became home to the Sunderland Flying Boat.
In 1945 it became a coastguard station until it was handed over to English Heritage.
The buildings to the right of the castle form the Calshot lifeboat station. The station is built on the grounds of the old military flying boat station. A lifeboat has been on this site site since 1970.
In the background is the Fawley Terminal where I have seen and photographed many ships whilst sailing down the Solent on one of the three Red Funnel ferries The site was originally developed in 1921 by the Atlantic Gulf and West Indies Petroleum Company.
Photograph taken 2 November 2013.