The Wittenham Clumps (Round Hill and Castle Hill IA hill fort)
The Wittenham Clumps are an enigmatic group of small hills in the Thames Valley of Oxfordshire and visible from the Ridgeway long distance path, much like the Didcot Power Station cooling towers until they were demolished. They consist of Round Hill, Castle Hill and its Iron Age fort and sometimes Brightwell Barrow to the South East, depending on who you ask!
Brightwell Barrow
Brightwell BA Barrow is sometimes counted as one of the clumps. It's situated South East to the main pair and slightly apart from them.