A rounded block of stone set in a large stone case, in which is an oval opening through which it can be seen. Built into the south wall of St. Swithin's Church on the north side of Cannon Street (O.S.).
Earliest mention: Stow says it is mentioned in a Gospel book given by King Athelstan to Christ's Church Canterbury (S. 226).
He describes it as on the south side of Cannon Street, where it is shown in Leake's map, opposite the south-west corner of St. Swithin's Church. But it appears from the Vestry Minute Book of St. Swithin's that in 1742 the stone commonly called London Stone was ordered to be removed and placed against the church on the east side of the door (Price, Rom. Pavement in Bucklersbury, p. 60).
In 1798 it was again removed and placed in its present position (p. 63).
It is oolite stone, such as was used by the Romans in their buildings (p. 62), and Strype tells us that it was much worn away and only a stump remaining, so that to preserve it it was cased over with stone "cut hollow underneath, so that the old Stone might be seen, the new one being over it, to shelter and defend the old venerable one" (Strype, ed 1720, I. ii. 200).
Stow tells us that in his time the stone was fastened very deeply into the ground with bars of iron and so strongly set that if carts ran against it the stone remained unshaken (S. 226).
Many suggestions have been made as to the origin of the stone : That it formed part of a large upright stone, or of a monument or building of the Romans (Price, p. 56). Camden calls it a "Milliarium" or milestone, from which the British high-roads radiated and from which the distances on them were reckoned, similar to the one in the forum at Rome. Wren agrees with this, but suggests that it was not simply a pillar but a building like the Milliarium Aureum at Constantinople (ib. 58-9).
Perhaps used for proclamations, etc., or a monument of heathen worship (Strype, ed. 1720, I. ii. 194).
The stone is frequently alluded to in London records to mark the situation of adjacent houses and property, etc., and appears from early times as a surname of London citizens.
The first Mayor of London was named Henricus Filius Eylwini de Londenestane, 1188 (Lib. de Antiq. Leg. p. 1), his house being situated near at hand.
A Dictionary of London. Henry A Harben. 1918.