Like the almshouse, Ohn's smithy belonged to Danyla. Its master smith, Ohn, was an outstanding craftsman who knew how to reforge Valyrian steel swords, and Danyla had sent someone to hire him from Qohor at great expense.
Although the smithy's storefront was unremarkable, its rear courtyard occupied an extensive stretch of land, reaching from the foot of Visenya Hill halfway up its slope.
One reason Danyla had purchased such a large tract of land was a mountain spring halfway up Visenya Hill. Its flow was small, but its water was sweet. However, the water seeped back into the mountain before flowing very far, so no one had ever discovered it.
Only after Ohn's smithy opened did a smith's apprentice stumble upon it. Danyla then used her connections to purchase all the surrounding land.
From then on, not only did the Red Keep have a supply of sweet spring water, but the smithy also had excellent water for quenching. Its spacious rear courtyard also made it convenient for Great Dragons such as Dreamfyre to land and take off.
Master Ohn was a man of ambition who had devoted his life to rediscovering the techniques for forging Valyrian steel. Danyla had sent someone to use that ambition to lure him to King's Landing.
Thus, a large furnace had been built in the rear courtyard specifically to allow Great Dragons to help melt steel.
Naturally, Danyla knew how to forge Valyrian steel, but she had no Great Dragon corpses available, and she still could not bring herself to sacrifice innocent people.
During this time, she and Master Ohn had devised a new approach: melt down Sweet Widow, then blend in other alloys to see whether they could produce more Valyrian steel.
For this purpose, Danyla had even requested a Great Dragon skeleton from