Haystack

This photo is currently dated to the 1910's, perhaps because Ewo's Mess, built in 1912-13 is seen in part on the left. However, there are some indications the pic was taken in the 1920's or later.

Firstly, the light-coloured, triangular-shaped, garden in the bottom-right foreground. Under max focus it can be seen to consist of a lawn surrounded by flowering bushes. Normally gardens are only laid out towards the end of construction, or following completion, of the building to which they belong. In this instance the building was No.10 & 11 The Peak, built sometime between 1920 and 1924, out of sight to the right.    

Now try to find Victoria Hospital away in the background. I think it's above the weird little hut between Ewo Mess and Edgehill, but I'm not certain (there's lots of research on the Victoria Hospital "place" page, but many photos have unfortunately been deleted). Just to its right is a dark building. It doesn't stand out well, but I think it's there and that it's the Hospital's Maternity Block, built from 1921-23. 

So the photo could have been taken in the 1920's.