Calshot Castle

Calshot Castle is a three-story circular fort made of Portland limestone, standing at the entrance of Southampton Water and marked by thick defensive walls and narrow windows. The structure was built strategically on a spit of land and features robust bastions to command the shipping lanes.

Henry VIII ordered the construction of this Device Fort between 1539 and 1540 to protect the coast against French and Spanish invasions. The facility was part of a larger defense system that was expanded and modernized over decades.

The fort hosted the prestigious Schneider Trophy seaplane competitions from 1929 to 1931, when the military site increasingly served sporting purposes. These events attracted aviators and spectators from around the world and made the location a center of aviation history.

The fort opens daily from April to October, with guided tours available hourly and parking at the nearby Calshot Activities Centre. Visitors should wear sturdy footwear as the paths on the spit are exposed and can be slippery in wet weather.

During World War I, the fortress was transformed into a seaplane base conducting anti-submarine patrols to protect British waters from German threats. This transformation shows how quickly the site adapted to changing military needs.

Location: Fawley

Inception: 1539

Made from material: Portland limestone

Part of: Device Forts

Website: https://english-heritage.org.uk/visit/places/calshot-castle

GPS coordinates: 50.81990,-1.30743

Latest update: December 6, 2025 17:40