NAVAN was the capital of Ulster for over two thousand years. Excavations in 1971 revealed the remains of a huge post built structure consisting of a series of concentric rings of posts, plus several 'avenues'. This structure is known as a temple, however, it is not certain the the post rings, which are up to 40m in diameter, represent a building. They may be alignments of some kind. ESME is being used to help build possible reconstructions of the structure in order to try and throw light on the problem. Navanr image9 is a winsom solid model showing the posts forming the structure. Ray-tracing has been used to cast the shadows. Navanr1 image9 is a view of looking through the post from the centre of the rings. Navan5 & Navan6 show views of a possible roofed reconstruction. Note that straw texturing has been added.