The Obelisco Agonalis ( 16.54 m), which stands in the centre of Piazza Navona, was commissioned by the emperor Domitian (r. 81-96). The obelisk originally stood near the Iseum (Temple of Isis) until the emperor Maxentius (r. 306-312) had it moved to the circus he had built on the Via Appia.
At some point in the middle-ages, the obelisk collapsed. In 1648 Pope Innocent X (r. 1644-1655) had it moved to Piazza Navona, where it became part of the Fontana dei Quattro Fiumi (Fountain of the Four Rivers), the creation of Gian Lorenzo Bernini (1598-1680). The 'Agonalis' obelisk is crowned with a bronze dove bearing a sprig of laurel in its beak, part of the heraldic alms of the pope’s family, the Pamphilj.
The base of the obelisk sports four inscriptions:
North face: OBELISCVM / AB IMP ANT CARACALLA ROMAM ADVECTVM / CVM INTER CIRCI CASTRENSIS RVDERA / CONFRACTVS DIV IACVISSET / INNOCENTIVS DECIMVS PONT OPT MAX / AD FONTIS FORIQ ORNATVM / TRANSTVLIT INSTAVRAVIT EREXIT / ANNO SAL MDCLI PONTIF VII. (For the embellishment of the fountain and the square, Innocent the Tenth, Pontifex Maximus, transported, restored and erected the obelisk brought to Rome by emperor Antoninus Caracalla, after it had lain broken into pieces amid the ruins of the Circus Castrensis, in the year of Salvation 1651, the seventh of his pontificate.)
East face: NOXIA AEGYPTIORVM MONSTRA / INNOCENS PREMIT COLVMBA / QVAE PACIS OLEAM GESTANS / ET VIRTVTVM LILIIS REDIMITA / OBELISCVM PRO TROPHEO SIBI STATVENS / ROMAE TRIVMPHAT. (The innocent dove subdues the harmful monsters of Egypt, bearing the olive of peace and crowned with the lilies of virtue, in setting up the obelisk as a trophy to herself she triumphs at Rome.)
South face: INNOCENTIVS DECIMVS PONT MAX / NILOTICIS AENIGMATIBS EXARATUM LAPIDEM / AMNIBVS SVBTER LABENTIBVS IMPOSVIT / VT SALVBREM / SPATIANTIBVS AMOENITATEM / SITIENTIBVS POTVM / MEDITANTIBVS ESCAM / MAGNIFICE LARGIRETVR. (Innocent the Tenth, Pontifex Maximus, set this stone, graven with the riddles of the Nile, atop the streams that flow below, that in grand style he might furnish wholesome delight for those who stroll, drink for those who thirst, sustenance for those who reflect.)
West face: INNOCENTIVS DECIMVS PONT MAX / NATALI DOMO PAMPHILIA / OPERE CULTVQ AMPLIFICATA / LIBERATAQ INOPPORTVNIS AEDIFICIIS / AGONALI AREA / FORVM VRBIS CELEBERRIMVM / MVLTIPLICI MAIESTATIS INCREMENTO / NOBILITAVIT. (Innocent the Tenth, Pontifex Maximus, on the occasion of improvements, both structural and aesthetic, to his ancestral Pamphilj home, and the clearing of Piazza Navona of unsuitable constructions, by a manifold increase of its grandeur ennobled the city's most famous square.)