Upton Towans

First glance they appear to be some kind of base for heavy duty yet portable plant, or, prefabricated buildings. laugh# laugh#

someone told me that they were part of the old dynamite works. EDIT: just found your other pics, treeve agrees.

The site was owned by The National Explosives Company.
Opened in 1888 to make mine dynamite, cordite, gelatine, nitro-glycerine and gelignite. The area of the site was 300 acres. Manufacture continued through WWI and was closed in 1919. It was used for explosives storage until 1960. Few building remnants exist. The site was cleared and carried by rail (on the Spur Line) and was finally closed in 1922.