Thor missile site at former RAF Harrington including the Pyrotechnic Store and Classified Storage Building to the West of the three emplacements.

The Thor missile site at the former RAF Harrington includes the Pyrotechnic Store and Classified Storage Building located to the west of three launch emplacements. This site is made of reinforced concrete bases and structures and is situated in an isolated area surrounded by farmland, southeast of where the airfield's runway used to be. The three launch emplacements are arranged in a unique linear configuration along a plateau. Although the compound is no longer intact, remnants can be traced; the concrete pad for the Launch Control cabins is to the east, while the Pyrotechnic Store and Classified Storage Building are to the west, protected by earthwork bunds.

The southern (no.1) and central (no.2) emplacements still retain most of their concrete base, blast walls, launcher erector mounting, fuel dump pit footings, and partially standing theodolite sheds. A part of a theodolite pillar leans against the shed of emplacement no.2. However, the concrete base of the northernmost emplacement (no.3) has been partially removed at the west end, and there has been additional loss of components, including the theodolite shed, although the blast walls and launcher erector mounting bolts remain.

To the west, the Classified Storage Building and Pyrotechnic Store are protected by an 'E' shaped earthwork bund. These buildings are constructed with metal frames and reinforced concrete panels. The Classified Storage Building is located south of the Pyrotechnic Store and features a tall vehicular entrance on its west elevation and a flat roof. The location of the Pyrotechnic Store is indicated on the accompanying map.

Additionally, to the east, there is a concrete pad for the launch control cabin and an associated fuel tank. Further east lies the ruinous power conversion building.