The Procession leaves the Tower lead by the Chief Warder. ***** The ancient custom of Beating the Bounds took place one again at the Tower of London. This old ceremony dafes back to Anglo Saxon days when maps were very rare, and it was customary once every year to march round the boundaries of each Parish.The Beating of the Boundary stones was performed by boys to ensure that the memory of each position survived as long as possible.The ceremony now takes place every three years.Choir Boys from the Royal Chapel of St. Peter an Vinvula, carry long willow wands and are led in procession by the Yeoman Warders. June 06, 1951. (Photo by Sport & General Press Agency, Limited).