The tank is a decommissioned Soviet T-34-85 battle tank originally used by the Czech army. The tank was used in the filming of Richard III (1995) and bought the same year by Russell Gray and installed in its current location.
The tank was the subject of a work by Cubitt Artists and Aleksandra Mir who painted it pink in 2002. The tank's livery is frequently changed.
Congrats to Seeking Masters for FTF and Pja_cz for STF