First Sight of the Iron Fortress

From C7.8, The River of the Seventh Stage. It illustrates C7.8.45–51:

C7.8.45
Then brave Esfandiyar mounted his steed,And bound his warrior’s belt with eager speed.
C7.8.46
He climbed a height; Ruyin Dezh lay below,Its iron ramparts cold in endless row.
C7.8.47
Three farsangs high, and forty broad its span;No clay or water showed to eye of man.
C7.8.48
The wall was broad enough for horsemen, fourAbreast, to ride along its iron floor.
C7.8.49
When he beheld that wonder, full in sight,He sighed and felt his heart grow dark as night.
C7.8.50
He said, “No strength can take so vast a place;This wretched road has brought me this disgrace.
C7.8.51
Alas for all our battles, toil, and pain;Regret is now the only fruit we gain.”