Theosophical society gardens in Adyar
Few people in Chennai seem to be aware of its existence. We just know it as that white gate on the way to Besant Nagar from Adyar. Inside those gates lies a world away from the city. It is open from 8-10 in the morning and 2-4 PM afternoon. So plan accordingly.
You can have a leisurely walk together amidst the groves, wondering if this is really Chennai. And the plus is, since it is so little known, there will hardly be a soul in sight
Here is the tripadvisor review - The Huddleston Gardens of Theosophical Society