Porticus Boni Eventus «Ammian. Marcellin. lib 19, in fin. P. Vittore nella Reg. IX di Roma»
The porticus Boni Eventus, built by Agrippa round the temple of Bonus Eventus, which he erected at the same time, between the thermae Agrippae and the theatre of Pompeius. Some remains of an ancient peperino wall, evidently of a temple, found on the site of the church of S. Maria in Monterone, have been thought to belong to this temple. At different times since the sixteenth century, five capitals of white marble of great size, 1.70 meters in height and 1.44 in width, have been found in an almost straight line 100 meters in length, between the church S. Maria in Monterone and the Teatro della Valle. These capitals were lying at an equal depth beneath the surface of the ground, and undoubtedly belonged to the porticus.