Here we see a platform arranged to form three sides of a square (tri-clinium
= "three reclining places room"). This platform would have been spread
with pillows to allow for comfortable reclining. There was
a strict protocol to the placement of diners. The family reclined
on the right, with the host at the top. The rest of the platform
was for guests, with the middle segment reserved for distinguished
guests. The spot on the middle section nearest the host on the right
hand section was the place for the most honored guest. Note that
this particular triclinium is intended to take advantage of warmer
weather; there would have been another more protected triclinium
in this house for colder weather. Below is a drawing of a dining
scene.
This drawing is from Connolly, P. and Dodge,
H., The Ancient City: Life in Classical Athens & Rome (Oxford
1998).