The ruins of Laodicea on the Lycus sit on a low plateau about ten kilometres south of Pamukkale, and despite being one of the most important cities of Roman Anatolia they are remarkably little visited. Excavation has accelerated since 2003, and the site now includes two cleared theatres, an enormous stadium, a re-erected gateway, the council chamber (bouleuterion), and one of the most complete surviving early Christian basilicas in Turkey.
Allow at least two hours. The Church of Laodicea, with its in-situ Byzantine mosaic pavements, is the standout — covered for protection by a modern roof and worth the detour on its own. The site is signposted off the highway between Pamukkale and Denizli and easy to combine with the main site for anyone with a rental car.