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Two large, impressive enclosures, or earthworks, can be seen at Gear and Caer Vallack, near Helford in Cornwall.
Sited on top of adjacent hills, they were thought by Victorian archaeologists to be Iron-Age hillforts. Though the local population knows them well, very little is understood about their origins.
Were these enclosures indeed prehistoric strongholds as the Victorian archaeologists surmised? Time Team decide to find out.
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