The grand house of Roman times - the domus - was a secluded space separated from the outside world. There were few doors and windows overlooking the street and in many cases there was only the door into the house. The atrium - a partially-roofed courtyard surrounded by rooms that lead off it - was the central feature of the house. A soft light, filtered through the atrium, illuminated the rooms. A small pond for gathering rain water made the atrium a pleasant place to spend time. Often a small altar, a lararium, was set up in honour of the gods who protected the home. Beyond the atrium was the peristylium, a small garden for rest and relaxation. The houses were decorated with simple floor tiles or decorated mosaics and painted murals.