By the end of WWII all except two distilleries had closed down.
The current Springbank distillery (built in 1828) has gradually incorporated parts of a few 'silent stills';
Argyll, Longrow, Rieclachan, Springside and Toberanrigh. Glen Gyle is another silent distillery in the area;
the name is now used for a 'new' distillery built by the owners of Springbank - more like a second plant, really.
Some other extinct distilleries in the Campbeltown area are Albyn, Ardlussa, Argyll, Benmore, Burnside, Campbeltown, Dalaruan, Dalintober, Glen Nevis, Glenside, Hazelburn, Kinloch, Kintyre, Lochhead, Lochruan,  Meadowburn, Rieclachan and Springside.
(You can find a full listing with background details at Ulf Buxrud's website: http://www.buxrud.se/lost.htm)

A century ago Campbeltown was the heartland of the whisky industry.
Back then, the city was famous as 'the capital of the whisky world' with
more than thirty active distilleries in the area. Many of them were founded
in the 19th century during one of the 'golden era's' of the Scotch whisky industry.
The Campbeltown area was blessed with lots of advantages that helped it become
the major whisky region of Scotland. Supplies of water, barley, peat and coal were abundant and the coastal location allowed distilleries to ship their whisky quickly and cheaply to the major markets. During the heydays huge steam ships delivered thousands of casks and bottles to Glasgow, London and the America's. But everything went pear-shaped at the start of the 20th century when overproduction started to take its toll.

Glengyle
Glen Scotia
Springbank

Single malts from Campbeltown:  

Campbeltown is probably the least known and positively the smallest Scottish
malt region. Named after the only real town on the Kintyre peninsula, there
are only two active distilleries left in the Campbeltown region; Springbank
and Glen Scotia - three if you count Glengyle.
But things used to be very different...

'The nearest place to nowhere,
and the furthest from anywhere...'
Isn't that a lovely recommendation for a travel
brochure? Well, there's some truth to the saying;
Campbeltown is very remote. It's actually the
part of Scotland that is closest to Ireland;
maybe a dozen miles across the Irish Sea.

The Springbank distillery also produces the
more heavily peated 'Longrow' malts, as well
as a new spirit under the name 'Hazelburn'.
Once again, these are second-hand names
of silent distilleries in the Campbeltown area.