Fort Wynyard was initially built as Kijk-in-de-pot Battery in 1795 by the Dutch. The Battery was disarmed in 1827 but was refurbished in 1862. At this time it was armed with at least four 68-pdr guns.
The Fort was upgraded in 1887 to mount:
- Three and Four Emplacements a 9.2-inch gun on HP mount
- One and Two Emplacements with 7-inch 6.5 ton RML guns on C pivots
This work was carried out by convict labour which kept the cost of the works to £9,518.
Plans dated 17th April 1891 detail the layout of these gun emplacements and associated magazines. (TNA MR 1/1309). The work started in 1887 were cont completed until April 1892
In 1900 the two 7-inch RML guns were replaced by two 6-inch Quick Fire Guns (A1 & A2 guns). The magazines for these two new 6-inch guns were underground between the two pits.
In 1910 four 3-pdr Quick Fire Guns were mounted in pairs, between the old 9.2-inch HP mounts.
Immediately to the rear of Fort Wynyard was a walled Laboratory that still stands. (TNA WO 78/3385 1891)
Fort Wynyard utilised the Defence Electric Light located at Mouille Point. By 1915 there were two DELs at this location.
Fort Wynyard was also the location for the alternate Port War Signal Station (PWSS) controlling all vessel movement in and out of Cape Town Harbour.
In 1914 the A1 and A2 Quick Fire Guns were replaced by two 6-inch Mark VII BL guns that were moved from Sierra Leone.