Arch of Janus

Completed Project
World Monuments Watch
Rome, Italy

 The Arch of Janus in the Forum Boarium is the only surviving quadrifrons arch in Rome.   This arch with four facades marked an important meeting place and crossroads in antiquity, where a busy port on the Tiber River met the slope of the Palatine Hill and led into the heart of the ancient city. Contrary to popular belief, the arch was not dedicated to the Roman god Janus, but it was named after the Latin word ianua, or door, which was itself derived from the name of the double-headed god of beginnings and transitions. The arch rests firmly on four broad pillars that support a cross vault. The structure is covered with marble slabs taken from the ruins of earlier buildings, and this construction technique has helped archaeologists date the structure to the second half of the fourth century. The keystones on each of the four sides are decorated with figures of Rome and goddesses of the Roman pantheon, while niches on the outward-facing sides of the four pillars contained other statues, now missing. Originally the arch supported a penthouse, which was removed in the nineteenth century, when it was mistaken for a medieval accretion, giving the arch the stout look that it has today.

A long-awaited reopening

Following the 1993 explosion of a car bomb in front of the nearby church of San Giorgio in Velabro, the arch was surrounded by a fence and remained innaccessible to the public. Black crusts and stains disfigured the appearance of the ancient arch, the last monument of the Forum Boarium that remains unrestored. The Arch of Janus was included on the 2016 World Monuments Watch to highlight the opportunity to further elevate the visibility of the Forum Boarium through its restoration. Thanks to support from American Express, WMF is collaborating with the Superintendency for the Coliseum and the Central Archaeological Area to complete a study and carry out the complete restoration of the arch. The Arch of Janus will then join the nearby temples of Hercules and Portunus, which were included on the World Monuments Watch in 1996 and 2006, respectively, and have since been restored thanks to significant support from American Express, the Robert W. Wilson Challenge to Conserve our Heritage, and the Selz Foundation. WMF’s long-standing partnership with the Italian Ministry of Culture has brought back to public attention an important chapter in the life of ancient Rome. 

A Watch Day celebration at the Forum Boarium

On May 26, 2017 a Watch Day event for the Arch of Janus highlighted the ensemble of monuments that make up the Forum Boarium, including the Temples of Hercules and Portunus, previously included on the Watch and restored with support from WMF. Activities for both adult and children included guided tours of the restored temples and a unique opportunity to climb the scaffolding surrounding the Arch of Janus for an up close view of the ongoing restoration. The public event concluded with a harp and violin concert with the arch as a backdrop for the musicians.

Five to Watch: Arch of Janus


Last updated: December 2020.

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