Mausoleum of Augustus

The Mausoleum of Augustus was the first of the monumental tombs for the Roman emperors. It was an enormous 4-story circular building. The lowest floor was 200 feet in diameter; above were terraces and on top of them, a statue of Augustus.

Source: A handbook of Architectural Styles, by Albert Rosengarten; translated by W. Collett-Sandars (1876).