Agricola Tower
Very little of the medieval Chester Castle remains today but this red sandstone tower has survived. 
Variously known as Julius Caesar's Tower, Julius Agricola's Tower and more recently, Agricola's Tower, this three-floored building was built c1150 as the gate tower for the inner bailey. The lower chamber was rebuilt after a fire in the early 14thC and has a fine stone vaulted ceiling and early English doorway. The upper chamber is a chapel of the late 12thC, named St Mary de Castro (St Mary's in the Castle.) It is a parallelogram in shape, measuring 19 feet 4 inches by 16 feet 6 inches, with a height of 16 feet 6 inches. 
The interior walls were decorated with fine frescoes which have been largely obliterated by damage to the plaster and numerous coats of lime through the years. These medieval paintings may well be some of the only known surviving wall paintings of Henry III's patronage or even of the last Norman earl.
When James II visited Chester in 1687 he attended Mass and received sacrament at the chapel. 
The medieval fabric of the building was refaced by Thomas Harrison during his rebuild of the castle in 1818.
When the tower ceased to be used for religious purposes in the 17thC, it was made use of as a magazine, a great quantity of weapons and gunpowder being stored here until 1921. The following year it reurned to its original use as the chapel of the Cheshire Regiment.