A trading port that flourished from the 15th to 19th centuries, drawing Chinese, Japanese, and later European merchants — the architecture still shows that mix, from Chinese assembly halls to the covered Japanese Bridge. The old quarter is walkable end to end, and best seen slowly rather than as a checklist.
The old quarter turns pedestrian-only most evenings, when the silk lanterns the town is known for are lit along the riverfront — a genuinely different atmosphere from the daytime version of the same streets, and worth timing a visit around.
A cluster of Hindu temple ruins built by the Champa kings between the 4th and 13th centuries, set in a jungle valley about an hour from Hoi An. Smaller in scale than Angkor but a genuinely important Cham religious site, and a UNESCO World Heritage listing in its own right.