It is located on Willis's Plateau at the northern end of the Upper Rock Nature Reserve, just southeast of Princess Anne's Battery.

Princess Royal's Battery is in Gibraltar, the British Overseas Territory at the southern end of the Iberian Peninsula.

[9] At that time, "nearly all the guns in Willis's were six-pounders, and in the journal of the siege it is mentioned that a three-pounder in Queen Anne's battery did great execution in the enemy's works.

"[13] That year, the guns at Queen's Anne's Battery were sufficiently effective during the thirteenth siege of Gibraltar that the Spanish officers were prompted to devise a plan to silence them.

[14][15][16] In February 1782, Princess Royal Battery was the site of the first use of Lieutenant George Koehler's depressing gun-carriage.

[18] Colonel John Drinkwater in his accounts claimed that the gun hit its target 28 times out of 30 when aimed at the Spaniard's San Carlos Battery.

In August 1782, during the Great Siege of Gibraltar, the Garrison strengthened the works at Willis's Plateau, and orders went out for the Princess Royal's Battery "to be caissoned with ship-timber.

On 21 July 1902, work began on a 6-inch breech loading Mark VII gun with barbette armour.

By November 1903, that 6-inch BL Mark VII gun had been mounted, as documented in a photograph (pictured above) of that date, with the installation finished by 24 May 1904.

Interior windows, lighting holes, along that corridor helped to avoid the risk of interaction of flame and gunpowder (D).