The New Student's Reference Work/Janus

Janus (jā′nŭs), an old Italian god, who was supposed to guard the gates of Rome. In every undertaking the pious Roman prayed for the blessing and help of Janus. He is represented with a scepter in his right hand and a key in his left, sitting on a golden throne. He has two faces, one youthful and the other aged, the one looking forward and the other backward. Numa devoted to him the passage close by the Forum at Rome. This passage, often called a temple, was simply a gateway, which was sacred and contained the statue of Janus. This was open in time of war, and closed in time of peace. So constant were the Roman wars, that this gateway was only three times closed in 700 years.