The Gymnasium at Olympia was a large, open air, quadrangle surrounded on all four sides by colonnades of the Doric order. Only the southern and eastern sides survive. They date to the second century BC. The River Kladeos has destroyed the western side. The gymnasium was used by runners and pentathlon athletes for training. Athletes trained in the nude. In bad weather, training took place under the eastern colonnade (210.51 meters) and the other three colonnades. Little of the gymnasium has been excavated. About 200 BC, a portico of the Corinthian order was built to join the gymnasium and the palaestra.