Flat Bastion

Flat Bastion extends southward from Charles V Wall with south-facing walls meeting at an obtuse angle to form a distinctive defensive structure. Inside the eastern section sits a magazine building that now serves as a geological research facility.

This structure was built between 1552 and 1627, representing centuries of early European fortification methods. By 1859 it received military upgrades with new artillery to help defend Gibraltar.

The structure was known as Baluarte de Santiago under Spanish rule and shows how Gibraltar's military design changed hands over time. You can see this layered history in the way it was built.

The magazine building in the eastern section can be visited by appointment, giving you access to see how this historical fortification worked. Plan ahead since visits are arranged in advance rather than dropping in anytime.

The magazine building was designed with specially made brick walls meant to absorb explosions from the powder stored inside. This heavy construction shows how engineers of that time dealt with storing extremely dangerous materials.

Location: Gibraltar

GPS coordinates: 36.13482,-5.35139

Latest update: December 14, 2025 14:23