Parthasarathy Temple is one of Chennai's great old Vaishnavite temples, standing in Triplicane a short walk from Marina Beach. Its name refers to Krishna as the charioteer of Arjuna, and the temple remains an active place of worship rather than a preserved monument.
The gopurams, pillared halls, and busy devotional rhythm make it one of the most worthwhile religious sites in central Chennai. Dress modestly and expect the visit to feel local and lived-in.