The Control Tower is another object that was left completely untouched when they decided to rip up the old US airbase. For several years the powers have been intending to do it up a bit and turn it into a visitors centre - cafe, toilets, screaming and unruly kids, and a view over the common from the glass thing at the top. This work must have started and stopped several times, and at one point it was shown as being on sale (no takers.)
At the current time, April 2018, it appears to be almost finished, at least cosmetically. Who knows what the internals offer.
The tower sits right in the main common car park and as such will be the first remaining evidence visitors see. There are, though, other access points to the common, and first-time visitors might be amazed and surprised to spot the tower off in the distance.
A Google Earth viewing, also showing the car park
A first distant view
Getting closer, a glimpse through the undergrowth
Somebody has, for reasons best known to themselves, decided to leave this decorative object nearby
Finally, we can get closeer
The shutters over the windows are new, and are part of the renovations needed to turn it into a visitors centre.
I believe those are the original antennae