The Basilica Ulpia was an ancient Roman civic building located in the Forum of Trajan. The Basilica Ulpia separates the temple from the main courtyard in the Forum of Trajan with the Trajan's Column to the northwest. It was named after Roman emperor Trajan whose full name was Marcus Ulpius Traianus.
It became perhaps the most important basilica after two ancient ones, the Basilicas Aemilia and Julia. With its construction, much of the political life moved from the Roman Forum to the Forum of Trajan. It remained so until the construction of the Basilica of Maxentius and Constantine.
Unlike later Christian basilicas, it had no known religious function; it was dedicated to the administration of justice, commerce and the presence of the emperor. It was the largest in Rome measuring 117 by 55 meters.