When King Solomon built the First Temple he knew that it would not be the Final Temple. Subsequently, he built subterranean passageways and storerooms in order to store the Temple Vessels, should the need arise. The Talmud relates (Tractates Yuma 62b and Horiyot 12a) that the most important of the vessels were hidden away by King Josiah, the grandson of Mennaseh, before the destruction of the First Temple, included in these were the Holy Ark.
