What is this?

[m3cs]

Strange dome shaped building in Slough. Cannot figure out from above or streetview what on earth it could be. Anyone know?

https://maps.app.goo.gl/zo9iwD4kVE7Ji3SA7?g_st=com...

[SuperNads]

Looking at old maps it's right on the site if an old pit/reservoir so it could be some sort of water storage or flood defence?

[FMOB]

MIB European Headquarters?

[The Rotrex Kid]

Covered reservoir :thumbup.

http://www.sopse.org.uk/ixbin/hixclient.exe?a=quer...

[m3cs]

Thank you

[Super Sonic]

Looks like some kind of retaining plunger.