1647. It is called Palace of forty columns, as there are many columns, and in Iranian, 40 means many. Incidentally, there are twenty columns, and these are reflected in the pool in front, which might also account for its name. The function of this palace was for holding religious-national ceremonies and royal festivals and for receiving royal ambassadors and guests. Its Persian Gardens are among the nine inscribed on the UNESCO World Heritage List. Contains some spectacular battle murals.