The short sides of the structure formed apses, while the main entrance was via three doorways on the long east front overlooking the Forum of Trajan, which was one meter below the level of the Basilica.

[4] The columns and the walls were of precious marbles; the 50 meter (164 ft) high roof was covered by gilded bronze tiles.The east façade featured a portico with three projecting porches.

[9] The Basilica Ulpia was first excavated by the occupying French government of Napoleon Bonaparte in 1813, after two convents on the site were demolished (Santo Spirito and di Santa Eufemia).

The excavations also uncovered the remains of the pavement made from rare marbles, which gradually disappeared over the course of the 19th century due to rapacious tourists.

[10] Clement VII removed several of the yellow giallo antico marble columns which once flanked the doorways of the structure to Saint Peter's Basilica, where they were erected in the transept, while one went to the Lateran Palace.

[10] Part of the foundation of the basilica continues today under the modern Via dei Fori Imperiali, a trunk road constructed during the rule of Benito Mussolini.