The London Stone is an historic landmark housed at 111 Cannon Street, across the river from Shakespeare’s Globe theatre. This building on Cannon Street, number 111, isn’t some grand museum or ancient historic structure; it’s a relatively new-build bank or investment centre, a standard office building, but at its foot, there is a strange little structure at ground level.

Directly above, it says “London Stone” and there are two plaques either side to tell passers-by what they are looking at: a modest chunk of oolitic limestone, measuring 53 cm x 43 x 30, apparently the remnants of a once much larger object that had stood for many centuries on the southern side of the street.

So, an old rock in the middle of the capital, but what’s the deal with the London Stone? What was it? Why is it so important? Watch the video to learn more!