The stone bearing the mark of Sir Christopher Wren was found near the site of an ancient wharf at Portland from whence stone was transported by sea and the River Thames for the building of the Cathedral. It was shipped to London in 1972 aboard the Sailing Barge MAY with other Portland Stone for restoration work and was received at the wharf by the Dean, and by the Master and Wardens of the Worshipful Company of Masons who were exercising the ancient right of inspection
