Why were roman chariot races ran counterclockwise?

Answer 1

Apart from coincidence - if it was the other way around you could ask why it was clockwise - it is suggested by Tertullian on the spectacles IX that everything in the chariot races had to do with references to the universe. The four colored teams symbolized the seasons, for example. In that case, the counter clockwise movement is the either the rotation of the earth around its axe, or the revolvement of the universe around the sun. As the obelisk is a symbol of the sun, they do run around the sun in the case of the circuses of Rome and Constantinople. Before the games started, there were also clown-like entertainers, dedicating the games to the sungod.

Remember that funeral rites consisted of the same movement, just like the Roman triumphs; and the same goes for the foundation of a new city [sulcus primgenius]. It must have been an important movement.