From the Council Floor we descend by the north-east staircase to the basement of the Tower, now lighted by electricity and divided into three rooms popularly known as the DUNGEONS. In the old days these were unlighted and could be reached only by the north-east staircase.
The Mortar Room contains old bronze mortars and two Burmese guns. At the south end is the Sub-Crypt of St. John's Chapel, entered by a doorway erroneously regarded as the cell called 'Little Ease,' where Guy Fawkes was confined, tied by his ankles and wrists to a ring in the floor. Edward I. is said to have imprisoned 600 Jews (men, women, and children) in the sub-crypt. In the Cannon Room are old iron and brass guns and a grotesque Lion of St. Mark, taken from a Venetian fort at Corfu. On the right is a well, 40 feet deep, dating from the 12th century.
Turning to the left, as we quit the White Tower, we pass some old cannon (mostly captured in the French wars) at its north-west angle, and arrive at the north end of TOWER GREEN, once the burial-ground of St. Peter's. A brass plate marks the Site of the Scaffold, used for the comparatively few executions within the Tower. Here suffered Anne Boleyn (1536), the Countess of Salisbury (1541), Catherine Howard (1542), Viscountess Rochford (1542), Lady Jane Grey (1554), and Robert Deyereux, Earl of Essex (1601). To the north is the church of St. Peter ad Vincula (shown on application to the warder on duty; closed on Saturday afternoon), rebuilt by Edward I. in 1305, probably on an earlier foundation of Henry I. (12th century), and restored after a fire in 1512. It has a good open timber roof and contains monuments to Constables of the Tower, a font of Edward I.'s time, and an organ brought from the Chapel Royal in Whitehall.
Most of those executed on Tower Hill were buried in the church or the adjoining burial-ground, though in many cases the bodies were removed elsewhere. Within the altar rails are buried Anne Boleyn, Catherine Howard, Lady Jane Grey and her husband Lord Guildford Dudley, the Dukes of Somerset, Northumberland, and Monmouth, the Earls of Arundel and Essex, the Countess of Salisbury, Viscount Rochford and his wife, and Sir Thomas Overbury. Elsewhere in the church lie Bishop Fisher, Sir Thomas More, and the Jacobite lords executed in 1747.
Visitors are freely admitted to the service on Sunday at 11 a.m., during which the great entrance and the Byward Tower are closed and a yeoman warder mounts guard. On Christmas Day, Easter, and Whitsunday the yeoman warders parade and march into the chapel bearing their halberds.