Built on the remains of an old Roman bath in the 16th century, the Meridian Line of the Basilica of St Mary of the Angels and the Martyrs was an act of one-upmanship.

Commissioned by the pope, the meridian-aligned sundial was a Gregorian victory over pagan time keeping.

Its location in the basilica was chosen for numerous practical reasons including the structure’s southern position, historic architecture, and high ceilings. The clock still works today, every day the sun lines up perfectly with the hole in the ceiling of the basilica casting a light that lands on the line precisely at noon. It can also determine the time of year based on where the light falls on the line.

Piazza della Repubblica, 00185, Rome Italy, Phone: +39-06-4-88-08-12

Campo de Fiori Casina Delle Civette Colosseum Galleria Borghese Galleria Sciarra Keats Shelley Memorial House Meridian Line of the Basilica of St Mary of the Angels and the Martyrs Museo Nazionale delle Pasta Alimentari (National Pasta Museum) Pantheon Piazza Venezia Pyramid of Cestius Quartiere Coppede Roman Forum Santa Maria Della Concezione Spanish Steps St. Peter’s Basilica The Mithraeum at Circus Maximus The Roman Guy Torre Argentina (Roman Cat Sanctuary) Katie Parla Trevi Fountain Vatican Museums Casa Mia Villa Borghese Gardens Zuccari Palace

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