Koodal Azhagar is one of the 108 Divya Desams — the holiest Vishnu temples for Tamil Vaishnavites — and is unusual in that the central shrine houses Vishnu in three forms simultaneously: standing, seated and reclining, on three levels of the same vimana.
The temple is much quieter than nearby Meenakshi and provides a useful pause in the middle of a day's sightseeing. The wooden roof structure of the main hall is original 16th-century carpentry, supported on tall stone pillars; you can see the lashings used to fix it together.