and the answer is………………
………..a Bee Shelter
This Bee Shelter is regarded by the International Bee Research Association as unique. Containing 28 bee boles built to house straw bee skeps, it dates to around 1850.
Here are some more examples of Bee Boles
Lost Gardens of Heligan, Cornwall courtesy wikipedia
Kellie Castle garden, Fife, Scotland courtesy Gwen and James Anderson
West Linton, Scotland courtesy Walter baxter
Thank you to everyone who gave it a go. It may be that this has introduced you to a new architectural feature to watch out for in the future!!!