One of Ephesus' star attractions and second only to the Library of Celsus, this ornate, Corinthian-style temple honours Trajan's successor and originally had a wooden roof when completed in AD 138. Note its main arch; supported by a central keystone, this architectural marvel remains perfectly balanced, with no need for mortar. The temple's designers also covered it with intricate decorative details and patterns: Tyche, goddess of chance, adorns the first arch, while Medusa wards off evil spirits on the second.
Sailors and traders in particular invoked Tyche, who was also the patroness of Ephesus, to protect them on their long journeys. After the first arch, in the upper-left corner is a relief of a man on a horse chasing a boar – a representation of Ephesus' legendary founder Androclus. On the right-hand arch are a band of Amazons, other possible founders. At shoulder height are Greek 'key' designs that represent the nearby Büyük Menderes River.