Wells Cathedral Clock

The picture above:
The famous Wells clock was probably in place by 1390. Bishop Ralph Erghum, who had previously been Bishop of Salisbury and had installed a clock there in 1386, seems to have brought his clockmaker with him to Wells. The Wells clock is unique because it still has its original medieval face, depicting a pre Copernican universe with the earth at its centre. When the clock strikes every quarter, jousting knights rush round above the clock and the Quarter Jack bangs the quarter hours with his heels. An outside clock opposite Vicars' Hall, placed there just over seventy years after is connected with the inside mechanism.
http://www.wellscathedral.org.uk/history/presentbuilding/theclock.shtml