Two tufo blocks 5488 sit underneath floor 5320 (which is associated with wall 5351, which sits slightly South West of 5488) and just slightly under 5355 in the North (which may indicate that floor 5305 did not extend as far South 5320). The lower block has not been fully excavated, nor has either of the blocks' Northern limits as they continue under the floors. These blocks which are possibly associated with 5487 and 5486 (also underneath the floor), certainly belong to an earlier phase than the cement walls and floor 5320, and probably floor 5305 and rubble wall 5400; it is unclear how they relate to the early phase represented by the large ashlar and tufo pavers 5321 or even earlier column bases 5450 and pavers 5493.