Temple of Vesta

The Temple of Vesta, the patron goddess of the domestic hearth, was first built by Numa Pompilius (753–673 BC), the second king of Rome.

See:

1. John Henry Middleton, "XV.—The Temple and Atrium of Vesta and the Regia", in: Archaeologia 49 (2), 1886, pp. 391–423.
2. Gilbert Gorski, James E Packer:  The Roman Forum: a reconstruction and architectural guide. New York, 2015
3. https://www.info.roma.it/monumenti_dettaglio.asp?ID_schede=572
4.