Is passover the oldest festival

Passover is 3325 years old, but our oldest traditions go back another 500 years, to the lifetime of Abraham. The oldest Jewish tradition is 3822 years old; and it retells how the young Abraham questioned the idolatrous indoctrination which was going on all around him.
Still older traditions recount the Creation, the life of Adam, etc.; but those may be viewed as being more of a general tradition than a Jewish one.