Kütahya's Great Mosque stands at the heart of the old town, close to the archaeology and tile museums. It was begun under Bayezid I and completed around 1401, then rebuilt in the late Ottoman period.
Inside, the mosque is spacious and fairly plain by Turkish standards, which makes the tilework around the mihrab stand out. It is a good stop not because it overwhelms you, but because it ties Kütahya's Ottoman history and ceramic tradition together in one quiet room.