In what country are the Pontine Marshes?

The Pontine Marshes, termed in Latin Pomptinus Ager by Titus Livius, Pomptina Palus (singular) and Pomptinae Paludes (plural) by Pliny the Elder, today the Agro Pontino in Italian, is an approximately quadrangular area of former marshland in the Lazio Region of central Italy.

The former marsh is a low tract of mainly agricultural land created by draining and filling, separated from the sea by sand dunes. The area amounts to about 80,000 ha (800 km2; 310 sq mi).

The marsh was an extensive alluvial plain at about sea level (some above, some below) created by the failure of the streams draining the mountains to find clearly defined outlets to the sea through the barrier dunes. Above sea level, it was a forested swamp; below, it was mud flats and pools. Sparsely inhabited throughout much of their history, the Pontine Marshes were the subject of extensive land reclamation work performed periodically. The tribe of the Volsci began with minor draining projects in the vicinity of Tarracina in connection with their occupation of it in the pre-Roman period.