The spandrels of the arch were especially awkward spaces and the different sizes of blocks used in these areas reveal the difficulties that the masons had in fitting blocks together. The way in which the columns were carved mainly from the same block as the section of wall behind can be seen here, except on the left where a separate block was inserted. Again, almost all of this work would seem to have been done in place to judge from the way the detailed figured scenes are carved across block divisions without figural discontinuity.
