The Brasov-transmitter [153 kHz] in Romania includes a strange fenced circle with a concrete block inside. There is no mast on it and on pictures from 2005 (Google Earth) there is also no mast visible.
Does anybody know what the purpose of that is/was?
45.754466719645386, 25.604889212299398
You can use Streetview to view the fence and the block in the middle. It is also shown in better quality in a drone video:

Marco (2022-03-18)