What does Amir find in chapter 21?

Amir finds his and Hassan's inscription: "Amir and Hassan. The Sultans of Kabul" (21.38).

There are a few things he finds so I'll go with one,

During halftime, Amir discovered the horrifying reason for the two deep holes in the ground; they were to be the graves of two accused adulterers, who would be stoned in front of the thousands of attendees.