The Cardiff Submarine Mining Station was built between 5th May 1886 and 4th February 1887, although the Test Room was still not operational by this date.
Contemporary plans show the Establishment was located just north of the Sea Lock on a dockyard that has now all be reclaimed. The approximate site of the Submarine Station is now occupied by the Belevista Care Home. The small strip of park, that currently runs parallel to the houses on Harrowaby Street, is the site of the old canal that rang alongside the mining station.
Further background information on Submarine Warfare can be seen here.
The Seven Volunteer Division, Submarine Miners was initially known as the 1st Gloucester Engineer Volunteers with three companies. In 1888 they became the Seven Volunteer Division, Submarine Miners, RE with four companies by 1900. These Volunteers also helped with the Defence Electric Lights at Pembroke Docks.
In 1907 they were converted to the Electrical Engineers with a strength of sixteen officers and two hundred and forty three other ranks..