Strange temple hidden in the woods

We got out today. Had a stroll (short one) around Lynford Arboretum.
We went on a different path to usual as that walk would be too long and discovered this.

The arboretum was originally part of the grounds of Lynford Hall, existing since the 16th century, burnt down several times rebuilt several times and now a hotel.  Interesting fact that I can not prove:- the exterior scenes of Rene's café from Allo Allo were filmed here.

The grounds were sold to the Forestry Commission and now is a wonderful area for walks, both in the arboretum with its specimen trees and the other parts with just normal trees.

After extensive research (I googled it) I found this is not a temple but a disused water tower. Oh well, it was a good idea whilst it lasted