The "Treasury" was probably constructed during the reign of the Nabatean ruler Aretas III Philhellene (82-62 B.C.). It is probably a temple and not actually a tomb.
The exterior of the lower storey has four free-standing and two engaged columns that support a classical-style architrave and triangular pediment. Behind these columns, there is a porch with a large central door that leads into the primary shrine room that probably contained a statue of the deity al-'Uzza (the Nabatean equivalent of Aphrodite). On the north (right) and south (left) sides of the porch, doors lead to side rooms.
The first phase of construction consisted of the four freestanding columns, with composite capitals that supported the protruding central architrave with the protruding low triangular pediment. The peak of the pediment is crowned with an acroterion.
The second phase of construction included the two attached columns, the large bas-relief figures behind them, and the two auxiliary rooms that lead off the porch.