<p>Temple of Dius Fidius (also identified with Semo and Sancus: Ov., <i>Fast</i>. 6.213-18), the god of oaths and treaties, located on the *Quirinal (Varro, <i>Ling</i>. 5.52: <i>apud aedem Dei Fidi</i>, 5.66: <i>Dius Fidius</i>; <i>Fast. Ven</i>., in Degrassi, <i>Inscr. Ital</i>. 13.2, 58, 465: DIO FIDIO IN COLLE) near the *Porta Sanqualis and Temple of *Quirinus (Livy 8.20.8). It was believed to have been built by Tarquinius Priscus and later dedicated by Spurius Postumius Albinus (Dion. Hal., <i>Ant. Rom.</i> 9.60.8), though no remains of the temple survive; the structure would have been open to the sky, given the nature of the deity (Varro, <i>Ling.</i> 5.66). An inscription found near S. Silvestro (<i>CIL</i> VI 568) allows the sanctuary to be located in the vicinity of the church.</p>