This foundation cylinder marked the restoration of the temple of the moon-god at Ur, by King Nabonidus. It ends with a prayer for himself and his son Belshazzar.
The text runs as follows: "And as for me, Nabonidus, the king of Babylon, protect me from sinning against your exalted god-head, and give me graciously a long life: and in the heart of Belshazzar, my first-born son, the off-spring of my loins, set the fear of your exalted god-head, so that he may commit no sin and that he may be satisfied with the fulness of life."
This is one of the first evidences for the historical existence of Belshazzar. Before the discovery of this cylinder, many scholars denied that Belshazzar was a name of a real historical king, as Nabonidus was known to be the last king of Babylon, when Cyrus the Persian took the city.