London Stone 111 Cannon Street London
London Stone is a historic stone that is now set within a Portland stone surround and iron grille on Cannon Street, in the City of London.
London Stone is a block of oolitic limestone and measures approximately 53 x 43 x 30 cm (21 x 17 x 12 inches). This material does not occur naturally in London, its nearest source being in Kent. It is thought to have originally been much larger. Speculation in the 17th and 18th centuries suggested it was either a milliarium, marking the central spot from which all distances were measured in Roman Britain or an object of Druidic worship, suggestions that are now generally dismissed as lacking any evidence.