There are three Stormcloak Military Camps which are set up temporarily as part of the Civil War:
Markarth Military Camp[]
This camp is set up just east of Markarth, across the bridge.
Solitude Military Camp[]
This camp is set up just west of Katla's Farm. It is only present during the Battle for Solitude.
Whiterun Military Camp[]
This camp is set up between Pelagia Farm and the Honningbrew Meadery. It is only present during the Battle for Whiterun.
There are two Imperial Military Camps which are set up temporarily as part of the Civil War: