The Cane Hill relay is situated on the water tower of the old Cane Hill mental asylum, which as been derelict since 1991.

The Cane Hill asylum itself is an extensive site which often seems to be the destination of various urban exploration groups. The site has been subject to many vandalism and arson attacks over the years, which have been known to affect the power supply to the transmitter.

These days the entire site is surrounded by a hostile looking fence and I believe there's manned security
patrols.

More pictures of the Cane Hill asylum itself can be found here and see also here for some aerial shots!