Original sentence: Almost immediately after the single ditch enclosure was expanded to 47 acres, work began on making the defences more elaborate.At the eastern end of the ridge and rising  above sea level, the site of the first hill fort was not the highest point along the ridge, although the highest point is the neighbouring Hog Hill and is only 3'3" (1m) higher.Their purpose on this site is uncertain however, since at 6'6" (2m) square they have been considered by archaeologists to be too small for dwellings; as a result, it has been concluded that these structures were probably granaries
Edited sentence: Almost immediately after the single ditch enclosure was expanded to , work began on making the defences more elaborate.At the eastern end of the ridge and rising  above sea level, the site of the first hill fort was not the highest point along the ridge, although the highest point is the neighbouring Hog Hill and is only  higher.Their purpose on this site is uncertain however, since at  square they have been considered by archaeologists to be too small for dwellings; as a result, it has been concluded that these structures were probably granaries