Flat Bastion Magazine is located within the upper left flank of Flat Bastion. The exact date for the construction of the original magazine is not known, but major works for the repair and improvement of Gibraltar’s defences was first proposed in 1808 by Lt. Col. Charles Holloway R.E. Maps and plans of the Flat Bastion before this time do not show a magazine within the bastion.

The defences along the Southern Front were improved by order of Lieutenant General Colin Campbell, Governor of Gibraltar around 1811, primarily in response to the threat of Napoleon’s armies during the Peninsular War – but these were much further south rather than along Charles V Wall.

In 1821, further alterations to the fortifications were made and a more ambitious plan for the re-alignment of the Line Wall were produced in 1826, but these were not carried out until 1841.

However, it appears that a very large magazine was indeed built within the Flat Bastion at some point during the 1820’s. Evidence for this can be found in a painting by Lieutenant H. A. West dated 1828 showing the Flat Bastion and magazine. The magazine is also included in a Piaget et Lailavoix lithograph of Gibraltar dated to around 1830 as well as in W.H. Smyth’s 1831 map of Gibraltar.

Lieutenant H. A. West - View from New Mole looking North, 1828.

Piaget et Lailavoix's map, 1830.

Gibraltar map by W.H. Smyth, 1831.

Major General Sir John Jones, writing in 1841, was highly critical of the deteriorated state of defence of the entire South Front and in particular the location of the magazine within the Flat Bastion, writing:

I am led to consider the Southern Defences more seriously than perhaps may have been thought necessary for some time past, I therefore beg to submit to your judgement whether it may not be expedient to re-establish Batteries in the Flanks of the Flat and Demi-Bastions so as to bring on some defence on the South Front, as also obstructions in the approach to the Gates.

His recommendation was as follows:

Item 4. To cover the Magazine and repair and restore the parapet and communications, and put the South Front into perfect order.

This front, built by Charles V of Spain, is of obsolete construction but the masonry being good, and the escarpe walls lofty, I should not have proposed more than the restoration of the decayed and damaged communications, had not a magazine, constructed a few years since on the left or upper flank of Flat Bastion, opened the escarpe wall, destroyed the flank defence and rendered imperative some additional walling as well to enclose the place and prevent the destruction of the building…

The magazine was built on scree breccia, with an underlying bedrock of limestone. The ground on which the magazine was constructed was relatively flat due to the implementation of quaternary wave-cut platforms.

Many of the original wooden supports are still present. The primary storage area for gunpowder has been described as "a room within a room" as it is surrounded by a narrow hallway. Windows are present at the sidewalls of the principal room. Bricks were utilized in the construction of the walls, to absorb the impact of explosions. The doors were fabricated from oak that supposedly dates back five or six centuries, well before the magazine was built.

Flat Bastion Magazine, 1861.

In 1873, the exposed front of the magazine was reinforced with a second layer of concrete as a precaution against the more powerful naval guns now being deployed by the new dreadnoughts of the time, especially the 100-ton guns of the Italian Navy. The thick casing on the magazine is similar to that encasing the Europa Tanks (old Casino), which was similarly reinforced during the same period. This extra layer and re-modelling of the entrances to the magazine can be seen in the Record Plan of the Flat Bastion Magazine.

The key stone above the magazine, dated to 1873, is therefore erected to commemorate the extension works and not the actual original magazine. Works on the protective covering began in late December 1870, completed in February 1873 at a cost of £2,551 - £28 under budget!

According to the site plan, the magazine could hold 3,652 barrels of gunpowder, divided into two separate powder bays.

Flat Bastion Magazine Record Plan.

While the Government of Gibraltar initially planned to develop it for parking, geology enthusiast Freddie Gomez and fellow geologist Paul Hopkins proposed to restore the building instead. The volunteers were also assisted by members of 150 (Yorkshire) Transport Regiment (Volunteers) from Doncaster and Kingston upon Hull who spent a day at the Flat Bastion Magazine. The regiment performed a variety of repairs on the historic building including refurbishment to the fire step, roof, railings, pillars, wall, and letterbox.

Once completed, the Flat Bastion Magazine became a geological research facility and exhibition centre, Geological Research Station and Lithology of Gibraltar, and displaying a large collection of rocks and minerals. While many of the displayed pieces come from his personal collection, many other samples were donated.

For his enthusiasm and single-minded dedication to the restoration and preservation of Flat Bastion Magazine, Freddie Gomez received the 2001 Senior Individual Heritage Award.

However, a disagreement between Freddie Gomez and Government led to the premises being returned to Government. It was later allocated as facilities to the Gibraltar Academy of Music & Performing Arts (GAMPA) transforming the premises into The Magazine Studio Theatre in 2018.

Keystone dated to 1873 when the original magazine was reinforced.

View from Elliot's Monument. Photographic views of Gibraltar, collected and arranged by Captain S Buckle RE