Question - Curious what might this be, any ideas?

[hewhowalksamongus]

What is this?
This is Military land and so not really a good idea to explore. Driving along the road you can see an open playing field with a fenced off pavilion at one end.
On the road side in the hedge is small brick tower. It looks almost like a domestic coal storage bunker or roadside salt storage. They are about 3-4' high with a gap at the top and a concrete top.
https://goo.gl/maps/TUSD7NxM34S2

But what I find interesting is that there are many of these brick towers placed in a grid pattern across the pitch area.

From the ariel picture you can just make out their shadows. Some are in the hedge along the road. If you look at this area is satellite view. I am having trouble attaching the link.
[MAP]https://www.google.com/maps/@51.2990138,-0.6740614,19z[/MAP]
https://www.google.com/maps/@51.2990138,-0.6740614,19z

What are these? I wouldn't be surprised of anything as there is a barrack on the other side of the rail and a WW2 pilbox down the road. But it is also quite a low wet area so could just be a reservoir.

 

[Yorrick]

They look like reservoir air vents. The dry patches on the grass look like a series of arched roofs that have been covered over.

Like this one https://www.28dayslater.co.uk/threads/aldershot-garrison-water-supply-hampshire-december-2013.86627/

 

[tumbles]

Wife Mine, For Sure

 

[Pirbright]

The area that you show is what the army use for the summer camp no more the concrete bases are old ablutions there's nothing underground
Aldershot reservoirs are other side of Aldershot near horse race track