The Mithraeum of Lucretius Menander was installed in the early 3rd century in an alley to the east of a Hadrianic building named after the solar god temple.
This Mithraic temple, aka Mithraeum of the Olympii, was discovered in the 15th century in Rome, although traces have been lost except for a few monuments with remarkable inscriptions.
The Mithraeum in the Chapel of the Three Naves was not linked to the cult of Mithras until recently because of a mosaic showing a pig, in the belief that it was an animal unfit for consumption in a temple of Eastern origin.