Avebury & the Marlborough Downs 64
Image by Chance

I wonder do you mean at SU11697003?
If so then the MAGIC site has this
http://www.magic.gov.uk/rsm/21731.pdf which says it's three confluent round barrows.

I've been able to get magic map to work!
PeteG

Well done Rhiannon. Pity it's not a long barrow but it's turned out to be something equally interesting.