Royal Navy Dockyard

From Wikipedia.

Another unfamiliar term for me.

A Royal Navy Dockyard is a harbor where commissioned British ships are stationed as well as ones where ships are overhauled or refitted.

In past years, the Royal Navy had a string of Dockyards around the world, but since World War II, the number has decreased to just four. 

Four of the Royal Navy Dockyards were classified as Great Dockyards: Portsmouth, Plymouth, Chatham and Glasgow.

Then, there were Large and Small Dockyards. Halifax was classified as Small.

--Brock-Perry